summaryrefslogtreecommitdiff
path: root/Master/texmf-dist/scripts/epspdf/epspdf.tlu
blob: 709a2d9b691e7187f7c78c26f704a8560cebbb4b (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486
1487
1488
1489
1490
1491
1492
1493
1494
1495
1496
1497
1498
1499
1500
1501
1502
1503
1504
1505
1506
1507
1508
1509
1510
1511
1512
1513
1514
1515
1516
1517
1518
1519
1520
1521
1522
1523
1524
1525
1526
1527
1528
1529
1530
1531
1532
1533
1534
1535
1536
1537
1538
1539
1540
1541
1542
1543
1544
1545
1546
1547
1548
1549
1550
1551
1552
1553
1554
1555
1556
1557
1558
1559
1560
1561
1562
1563
1564
1565
1566
1567
1568
1569
1570
1571
1572
1573
1574
1575
1576
1577
1578
1579
1580
1581
1582
1583
1584
1585
1586
1587
1588
1589
1590
1591
1592
1593
1594
1595
1596
1597
1598
1599
1600
1601
1602
1603
1604
1605
1606
1607
1608
1609
1610
1611
1612
1613
1614
1615
1616
1617
1618
1619
1620
1621
1622
1623
1624
1625
1626
1627
1628
1629
1630
1631
1632
1633
1634
1635
1636
1637
1638
1639
1640
1641
1642
1643
1644
1645
1646
1647
1648
1649
1650
1651
1652
1653
1654
1655
1656
1657
1658
1659
1660
1661
1662
1663
1664
1665
1666
1667
1668
1669
1670
1671
1672
1673
1674
1675
1676
1677
1678
1679
1680
1681
1682
1683
1684
1685
1686
1687
1688
1689
1690
1691
1692
1693
1694
1695
1696
1697
1698
1699
1700
1701
1702
1703
1704
1705
1706
1707
1708
1709
1710
1711
1712
1713
1714
1715
1716
1717
1718
1719
1720
1721
1722
1723
1724
1725
1726
1727
1728
1729
1730
1731
1732
1733
1734
1735
1736
1737
1738
1739
1740
1741
1742
1743
1744
1745
1746
1747
1748
1749
1750
1751
1752
1753
1754
1755
1756
1757
1758
1759
1760
1761
1762
1763
1764
1765
1766
1767
1768
1769
1770
1771
1772
1773
1774
1775
1776
1777
1778
1779
1780
1781
1782
1783
1784
1785
1786
1787
1788
1789
1790
1791
1792
1793
1794
1795
1796
1797
1798
1799
1800
1801
1802
1803
1804
1805
1806
1807
1808
1809
1810
1811
1812
1813
1814
1815
1816
1817
1818
1819
1820
1821
1822
1823
1824
1825
1826
1827
1828
1829
1830
1831
1832
1833
1834
1835
1836
1837
1838
1839
1840
1841
1842
1843
1844
1845
1846
1847
1848
1849
1850
1851
1852
1853
1854
1855
1856
1857
1858
1859
1860
1861
1862
1863
1864
1865
1866
1867
1868
1869
1870
1871
1872
1873
1874
1875
1876
1877
1878
1879
1880
1881
1882
1883
1884
1885
1886
1887
1888
1889
1890
1891
1892
1893
1894
1895
1896
1897
1898
1899
1900
1901
1902
1903
1904
1905
1906
1907
1908
1909
1910
1911
1912
1913
1914
1915
1916
1917
1918
1919
1920
1921
1922
1923
1924
1925
1926
1927
1928
1929
1930
1931
1932
1933
1934
1935
1936
1937
1938
1939
1940
1941
1942
1943
1944
1945
1946
1947
1948
1949
1950
1951
1952
1953
1954
1955
1956
1957
1958
1959
1960
1961
1962
1963
1964
1965
1966
1967
1968
1969
1970
1971
1972
1973
1974
1975
1976
1977
1978
1979
1980
1981
1982
1983
1984
1985
1986
1987
1988
1989
1990
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000
2001
2002
2003
2004
2005
2006
2007
2008
2009
2010
2011
2012
2013
2014
2015
2016
2017
2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
2028
2029
2030
2031
2032
2033
2034
2035
2036
2037
2038
2039
2040
2041
2042
2043
2044
2045
2046
2047
2048
2049
2050
2051
2052
2053
2054
2055
2056
2057
2058
2059
2060
2061
2062
2063
2064
2065
2066
2067
2068
2069
2070
2071
2072
2073
2074
2075
2076
2077
2078
2079
2080
2081
2082
2083
2084
2085
2086
2087
2088
2089
2090
2091
2092
2093
2094
2095
2096
2097
2098
2099
2100
2101
2102
2103
2104
2105
2106
2107
2108
2109
2110
2111
2112
2113
2114
2115
2116
2117
2118
2119
2120
2121
2122
2123
2124
2125
2126
2127
2128
2129
2130
2131
2132
2133
2134
2135
2136
2137
2138
2139
2140
2141
2142
2143
2144
2145
2146
2147
2148
2149
2150
2151
2152
2153
2154
2155
2156
2157
2158
2159
2160
2161
2162
2163
2164
2165
2166
2167
2168
2169
2170
2171
2172
2173
2174
2175
2176
2177
2178
2179
2180
2181
2182
2183
2184
2185
2186
2187
2188
2189
2190
2191
2192
2193
2194
2195
2196
2197
2198
2199
2200
2201
2202
2203
2204
2205
2206
2207
2208
2209
2210
2211
2212
2213
2214
2215
2216
2217
2218
2219
2220
2221
2222
2223
2224
2225
2226
2227
2228
2229
2230
2231
2232
2233
2234
2235
2236
2237
2238
2239
2240
2241
2242
2243
2244
2245
2246
2247
2248
2249
2250
2251
2252
2253
2254
2255
2256
2257
2258
2259
2260
2261
2262
2263
2264
2265
2266
2267
2268
2269
2270
2271
2272
2273
2274
2275
2276
2277
2278
2279
2280
2281
2282
2283
2284
2285
2286
2287
2288
2289
2290
2291
2292
2293
2294
2295
2296
2297
2298
2299
2300
2301
2302
2303
2304
2305
2306
2307
2308
2309
2310
2311
2312
2313
2314
2315
2316
2317
2318
2319
2320
2321
2322
2323
2324
2325
2326
2327
2328
2329
2330
2331
2332
2333
2334
2335
2336
2337
2338
2339
2340
2341
2342
2343
2344
2345
2346
2347
2348
2349
2350
2351
2352
2353
2354
2355
2356
2357
2358
2359
2360
2361
2362
2363
2364
2365
2366
2367
2368
2369
2370
2371
2372
2373
2374
2375
2376
2377
2378
2379
2380
2381
2382
2383
2384
2385
2386
2387
2388
2389
2390
2391
2392
2393
2394
2395
2396
2397
2398
2399
2400
2401
2402
2403
2404
2405
2406
2407
2408
2409
2410
2411
2412
2413
2414
2415
2416
2417
2418
2419
2420
2421
2422
2423
2424
2425
2426
2427
2428
2429
2430
2431
2432
2433
2434
2435
2436
2437
2438
2439
2440
2441
2442
2443
2444
2445
2446
2447
2448
2449
2450
2451
2452
2453
2454
2455
2456
2457
2458
2459
2460
2461
2462
2463
2464
2465
2466
2467
2468
2469
2470
2471
2472
2473
2474
2475
2476
2477
2478
2479
2480
2481
2482
2483
2484
2485
2486
2487
2488
2489
2490
2491
2492
2493
2494
2495
2496
2497
2498
2499
2500
2501
2502
2503
2504
2505
2506
2507
2508
2509
2510
2511
2512
2513
2514
2515
2516
2517
2518
2519
2520
2521
2522
2523
2524
2525
2526
2527
2528
2529
2530
2531
2532
2533
2534
2535
2536
2537
2538
2539
2540
2541
2542
2543
2544
2545
2546
2547
2548
2549
2550
2551
2552
2553
2554
2555
2556
2557
2558
2559
2560
2561
2562
2563
2564
2565
2566
2567
2568
2569
2570
2571
2572
2573
2574
2575
2576
2577
2578
2579
2580
2581
2582
2583
2584
2585
2586
2587
2588
2589
2590
2591
2592
2593
2594
2595
2596
2597
2598
2599
2600
2601
2602
2603
2604
2605
2606
2607
2608
2609
2610
2611
2612
2613
2614
2615
2616
2617
2618
2619
2620
2621
2622
2623
2624
2625
2626
2627
2628
2629
2630
2631
2632
2633
2634
2635
2636
2637
2638
2639
2640
2641
2642
2643
2644
2645
2646
2647
2648
2649
2650
2651
2652
2653
2654
2655
2656
2657
2658
2659
2660
2661
2662
2663
2664
2665
2666
2667
2668
2669
2670
2671
2672
2673
2674
2675
2676
2677
2678
2679
2680
2681
2682
2683
2684
2685
2686
2687
2688
2689
2690
2691
2692
2693
2694
2695
2696
2697
2698
2699
2700
2701
2702
2703
2704
2705
2706
2707
2708
2709
2710
2711
2712
2713
2714
2715
2716
2717
2718
2719
2720
2721
2722
2723
2724
2725
2726
2727
2728
2729
2730
2731
2732
2733
2734
2735
2736
2737
2738
2739
2740
2741
2742
2743
2744
2745
2746
2747
2748
2749
2750
2751
2752
2753
2754
2755
2756
2757
2758
2759
2760
2761
2762
2763
2764
2765
2766
2767
2768
2769
2770
2771
2772
2773
2774
2775
2776
2777
2778
2779
2780
2781
2782
2783
2784
2785
2786
2787
2788
2789
2790
2791
2792
2793
2794
2795
2796
2797
2798
2799
2800
2801
2802
2803
#!/usr/bin/env texlua

kpse.set_program_name('texlua')

-- epspdf conversion utility

-- 0.6.0: first texlua version
-- 0.6.1: allow TeX installation on path with spaces
-- 0.6.2: compatibility fix for luatex 0.81
-- 0.6.3: compatibility fixes for luatex 0.9x

ep_version = '0.6.3'
ep_copyright = '2006, 2008, 2009, 2010, 2011, 2013, 2014, 2015, 2016'

--[[

Note.
TeX code for cropping pdfs adapted from Heiko Oberdiek's pdfcrop utility

Program structure

- early initialization
- functions for:
  - error handling
  - file- and path utilities
  - other general utilities
  - infrastructure: logging and temporary files
  - reading and writing settings
  - gui function
  - boundingboxes
  - manipulating [e]ps- and pdf files
- the PsPdf object:
  - creator functions
  - boundingbox handling
  - one-step conversion methods
  - any_to_any method
- main initialization section:
  - collecting system information
  - infrastructure: setting up logging and temp directory
  - settings:
    - defining settings-, descriptions-, options- and auxiliary tables
    - read settings
    - defining commandline options and help function
    - parsing commandline and performing non-conversion options
- calling any_to_any
- finishing up

all calls to external programs work on temporary files with a simple
generated filename. The current directory is a newly-created
temporary directory. So no need to quote names of input- and output
filenames.

POSSIBLE EXTENSIONS

- duplicating epstopdf options
- custom options for gs and pdftops

--]]

-- some general utilities and globals ---------------------------

-- early initializations

eol = false
path_sep = false
if os.type=='unix' then
  eol='\n'
  path_sep = ':'
else
  eol='\r\n'
  path_sep = ';'
end

bufsize=16000 -- for reading and writing  files

-- these `declarations' are not really needed;
-- they are here mainly for my own peace of mind

from_gui = false -- whether epspdf is run from the epspsdtk gui

cwd = ''

-- Windows: miktex, TL or neither.
-- Actual values determined during system-dependent initialization
is_miktex = false
is_tl_w32 = false
-- recent versions of miktex include pdftops
auto_psp = true -- configuration of pdftops_prog not needed or not allowed

-- some global file- and directory names
gs_prog = false
pdftops = false
epsdir = false
rcfile = false
logfile = false
tempdir = false
tempfiles = {}
-- childpath = false
-- os.getenv('path') returns the parents path,
-- so we need to keep track ourselves of the child path

options = false -- actual conversion options
settings = false -- persistent settings; may be stored in config file
descriptions = false -- help strings for settings
gs_options = false
pdf_options = false
pdf_tail_options = false
ps_options = false
gray_options = false

-- logging ------------------------

-- we open and close the logfile anew for each write.
-- failure to open constitutes no error.

function print_log(s)
  local f = io.open(logfile, 'a')
  if f then
    f:write(s,eol)
    f:close()
  end
  if from_gui then
    print(s) -- intercepted by the gui
  end
end

function write_log(s)
    print_log(string.format('%s %s',
        os.date('%Y/%m/%d %H:%M:%S', os.time()), s))
end

function log_cmd(cmd)
  write_log('[' .. table.concat(cmd, '] [') .. ']')
end

-- error- and debug -------------------------

-- Simple-minded error handling. At most, we call a function which
-- tries to write the error message to log before re-raising the error.

-- When run from the Tcl/Tk gui, this gui will capture error messages.

function errror(mess)
  if logfile then pcall(write_log, mess) end
  -- ignore result of pcall: we can do nothing about failure
  error(mess, 2)
end

function warn(mess)
  if logfile then write_log(mess) end
  print(mess)
end

function dbg(mess)
  if options.debug then
    warn(mess)
  end
end

--[[

function dbg_opt()
  if options.debug then
    local mess = ''
    for _, k in ipairs({'bbox', 'gray', 'page'}) do
      mess = mess.. ' ' .. k .. ': ' .. tostring(options.k)
    end
    dbg(mess)
  end
end

--]]

-- file- and path utilities ----------------

function ep_shortname(path)
  if os.type=='unix' then
    return path
  else
    -- shortname appears not to work under miktex
    -- so return original path as a fallback
    local sp = lfs.shortname(path)
    return sp or path
  end
end

-- prepend or append dir to path if necessary
function maybe_add_path(dir, append)
  local dircmp = path_sep .. dir .. path_sep
  local pathcmp = path_sep .. kpse.var_value('PATH') .. path_sep
  -- case folding
  if os.name=='windows' or os.name=='cygwin' or os.name=='macosx' then
    dircmp = string.lower(dir)
    pathcmp = string.lower(pathcmp)
  end
  -- slash flipping
  if os.type=='windows' then
    pathcmp = (string.gsub(pathcmp, '/', '\\'))
    dircmp = (string.gsub(dircmp, '/', '\\'))
  end
  if not string.find(pathcmp, dircmp, 1, true) then
    if not append then -- prepend
      os.setenv('PATH', dir..path_sep..kpse.var_value('PATH'))
    else -- append
      os.setenv('PATH', kpse.var_value('PATH')..path_sep..dir)
    end
  end
end

function fw(path)
  if os.type=='windows' then
    return string.gsub(path, '\\', '/')
  else
    return path
  end
end

function absolute_path(path)

  --[[ Return absolute normalized version of path, interpreted
  from the directory from where the program was called.

  We use the fact that lfs.currentdir() always returns an absolute and
  normalized path. So we go to the parent directory of path, ask for
  the current directory and then combine the current directory with
  the base filename.

  On windows, texlua has no trouble cd-ing into a UNC path.

  The function returns nil if there is no valid parent path.
  This might be an issue if path is a directory,
  but we shall apply this function only on files.
  It is ok if path itself does not exist. --]]

  path = fw(path)

  local present_dir = fw(lfs.currentdir())

  lfs.chdir(cwd)

  local parentdir
  local filename

  if string.match(path, '/') then
    parentdir, filename = string.match(path,'^(.*)/([^/]*)$')
    if parentdir=='' then
      parentdir = '/'
      -- on unix, this is an absolute path. on windows, it is not
      if os.type=='windows' then
        lfs.chdir('/')
        parentdir = fw(lfs.currentdir())
      end
    elseif os.type=='windows' and string.match(parentdir,'^[a-zA-Z]:$') then
      parentdir = string.sub(parentdir,1,2)..'/'
    else
      if not lfs.chdir(parentdir) then
        parentdir = nil
      else
        parentdir = fw(lfs.currentdir())
      end
    end
  elseif os.type=='windows' and string.match(path,'^[a-zA-Z]:') then
    -- windows: d:file
    parentdir = string.sub(path,1,2)
    if not lfs.chdir(parentdir) then
      parentdir = nil
    else
      parentdir = fw(lfs.currentdir())
      filename = string.sub(path,3)
    end
  else
    parentdir = fw(lfs.currentdir())
    filename = path
  end
  lfs.chdir(present_dir)
  if not parentdir then
    return nil
  elseif string.sub(parentdir,-1)=='/' then
    return parentdir..filename, parentdir
  else
    return parentdir..'/'..filename, parentdir
  end
end -- absolute_path

-- check whether prog is on the searchpath.
-- we need it only under unix,
-- so we save ourselves the trouble of accommodating windows.
-- we return the original string, although we only need a yes or no answer

function find_on_path (prog)
  if os.type ~= 'unix' then
    errror('find_on_path: this is a unix-only function')
  end
  for d in string.gmatch(os.getenv('PATH'),  '[^:]+') do
    if lfs.isfile(d..'/'..prog) then
      return prog
    end
  end
  return false
end -- find_on_path

-- On Windows, we do not count so much on the existing searchpath
-- so is_prog tests whether the file exists and is an exe file.

function is_prog (path)
  -- 1. test for and if necessary add extension
  -- 2. test for existence
  -- 3. returns either false or absolute path
  if os.type ~= 'windows' then
    errror('is_prog: this is a Windows-only function')
  end
  if not path then
    return false
  end
  if not string.lower(string.sub(path,-4,-1))=='.exe' then
    path = path..'.exe'
  end
  path = absolute_path(path)
  if not (path and lfs.isfile(path)) then
    return false
  else
    return path
  end
end -- is_prog

function dir_writable(d)
  -- because directory attributes do not tell the whole story,
  -- we actually try to create a file in the directory.
  if not lfs.isdir(d) then
    return false
  end
  -- try to create a new file, write to it and delete it afterwards
  for i=1,1000 do
    local s = d .. '/' .. tostring(i)
    if not lfs.isfile(s) then
      local fh = io.open(s, "w")
      if fh then
        fh:write('test')
        fh:close()
        if lfs.isfile(s) then
          if lfs.attributes(s, 'size') > 0 then
            os.remove(s)
            return true
          else
            os.remove(s)
            return false -- open and write resulted in empty file
          end -- lfs.attributes
        else
          return false -- open and write did not result in a file
        end -- lfs.isfile
      end -- fh
      return false -- filename available; could not open for write
    end -- not lfs.isfile
  end -- for
  return false
end

function system_tempdir ()
  local d
  if os.type=='windows' then
    d = os.getenv('TEMP')
    if not d then
      d = os.getenv('TMP')
    end
  else
    d = os.getenv('TMPDIR')
    if not d then
      d = '/tmp'
    end
  end
  -- if d then dbg('system tempdir: '..d) end
  -- cygwin: $TEMP=/tmp, root '/' being root of cygwin installation
  if d and not dir_writable(d) then
    dbg('unfortunately, '..d..' not writable')
    d = false
  end
  return d
end

-- other general utilities ---------------------------

-- check whether el occurs in array lst
function in_list (el, lst)
  if not lst then return false end
  for _,p in ipairs(lst) do
    if el == p then
      return true
    end
  end
  return false
end -- in_list

-- remove leading and trailing, but not embedded spaces
function strip_outer_spaces(s)
  s = string.gsub(s, '%s*$', '')
  s = string.gsub(s, '^%s*', '')
  return s
end -- strip_outer_spaces

function join(t, sep, lastsep)
  -- there is a table function concat which does this,
  -- but without optional different lastsep
  if t==nil or #t<1 then return '' end -- or should we return nil?
  local s = t[1]
  for i=2,#t do -- ok if #t<2
    if i==#t and lastsep then
      s = s .. lastsep .. t[i]
    else
      s = s .. sep .. t[i]
    end
  end
  return s
end -- join

-- combine several tables into one.
-- the parameter is a table of tables.
function tab_combine (t)
  local res = {}
  for _,tt in ipairs(t) do
    for __, ttt in ipairs(tt) do
      table.insert(res, ttt)
    end
  end
  return res
end -- tab_combine

-- Copy a file in chunks, with optional length and offset.
-- Since files may be very large, we copy them piecemeal.
-- An initial chunk of size bufsize should be plenty to include
-- any interesting header information.

function slice_file(source, dest, len, offset, mode)
  -- The final three parameters can be independently left out by
  -- specifying false as value
  -- Assume caller ensured parameters of correct type.
  -- We do not allow negative offsets.
  local sz = lfs.attributes(source, 'size')
  if not offset then
    offset = 0
  elseif offset>sz then
    offset = sz
  end
  if not len or len>sz-offset then
    len = sz - offset
  end
  if not mode then mode = 'wb' end
  -- dbg('copying '..len..' bytes of '..source..' to '..dest..' from '..offset
  --       ..' in '..mode..' mode')
  local buffer=''
  local s=io.open(source, 'rb')
  s:seek('set', offset)
  local copied = 0
  local d=io.open(dest, mode)
  if not d then errror('slice_file: failed to copy to '..dest) end
  local slen = len
  while slen>0 do
    if slen>=bufsize then
      buffer = s:read(bufsize)
      slen = slen - bufsize
    else
      buffer = s:read(slen)
      slen = 0
    end
    if not d:write(buffer) then
      errror('slice_file: failed to copy to '..dest)
    end
  end
  s:close()
  d:close()
end -- slice_file

function move_or_copy(source, dest)
  if lfs.isfile(dest) and lfs.attributes(dest, 'size')>0 then
    warn('Removing old '..dest)
    os.remove(dest) -- in case of failure, go ahead anyway
  end
  if not os.rename(source, dest) then
    slice_file(source, dest) -- bails out on failure
    local ok, err_mess = os.remove(source)
    if not ok then
      warn('Failed to remove old ' .. source .. ': ' .. err_mess)
    end
  end
end

-- temporary files ----------------------------------------

-- tempdir = false -- will be created later and chdir-ed into
-- tempfiles initialized early to empty table

-- We just name our temporary files nn.<ext> with successive nn.
-- We cannot exclude that another process uses our tempdir
-- so we have to first check for each new file whether it already exists.
-- Epspdf does all the real work from the temp directory.

function mktemp(ext)
  local froot, fname, f, g
  for i=0,99 do
    froot = string.format('%02d.', i)
    fname = froot..ext
    -- dbg('New temp file '..fname..'?')
    if ext~='tex' then
      if not lfs.isfile(fname) then
        -- dbg(fname..' available')
        f = io.open(fname, 'wb')
        if not f then
          errror('Cannot create temporary file '..fname)
        end
        f:close()
        table.insert(tempfiles, fname)
        return froot..ext -- no need to record pdf name
      end
    else
      -- tex; we also need a pdf
      if not lfs.isfile(fname) and not lfs.isfile(froot..'pdf') then
        local f = io.open(fname, 'wb')
        if not f then
          errror('Cannot create temporary file '..fname)
        end
        f:close()
        table.insert(tempfiles, fname)
        fname = froot..'pdf'
        g = io.open(fname, 'wb')
        if not g then
          errror('Cannot create temporary file '..fname)
        end
        g:close()
        table.insert(tempfiles, fname)
        table.insert(tempfiles, froot..'log')
        return froot..ext -- no need to record pdf name
      end
    end -- if
  end -- for
  errror('Cannot create temporary file in '..tempdir)
end

function waitasec()
  -- stupid windows file locking
  if os.type=='windows' and (tonumber(os.uname().version) or 0)>=6 then
    os.execute('timeout /t 1 /nobreak >nul')
  elseif os.type=='windows' then
    os.execute('ping -n 1 localhost >NUL')
  -- else do nothing
  end
  -- error checking pointless
end

function cleantemp()
  lfs.chdir(tempdir)
  if os.type=='windows' then waitasec() end
  for _,f in ipairs(tempfiles) do
    if lfs.isfile(f) then
      local success, mess = os.remove(f)
      if not success then write_log(mess) end
    end
  end
  local empty = true
  for f in lfs.dir('.') do
    if f ~= '.' and f ~= '..' then
      empty = false
      write_log('Temp dir '..tempdir..' contains '..f..' therefore not removed')
      break
    end
  end
  if os.type=='windows' then waitasec() end
  lfs.chdir('..')
  if empty then
    local res, mess
    res, mess = lfs.rmdir(tempdir)
    if not res then
      write_log('Failed to remove empty '..tempdir..'\n'..mess)
    end
  end
end

-- epsdevice -----------------------

function epsdevice()
  local gh = io.popen(gs_prog..' -help')
  local s = gh:read("*a")
  gh:close()
  if string.find(s,'eps2write') then
    return 'eps2write'
  elseif string.find(s,'epswrite') then
    return 'epswrite'
  else
    return false
  end
end

-- settings -----------------------

function write_settings (file)
  local f
  if file then
    f = io.open(file, 'wb')
    if not f then
      return
    end
  else -- stdout to be captured by epspdftk
    f = io.output()
    if os.type=='windows' and not auto_psp then
      f:write('psp_config = yes', eol)
    end
  end
  for k, v in pairs(settings) do
    if k ~= 'pdftops_prog' or os.type=='windows' then
      if descriptions[k] and file then
        f:write(eol, '# ', descriptions[k], eol)
      end
      f:write(k, ' = ', tostring(v), eol)
    end
  end
  if file then
    f:close()
  end
end

function read_settings(file)
  -- read and interpret rcfile
  -- we shall ignore illegal entries.
  local contents
  local f
  if file then
    f = io.open(rcfile, 'rb')
    if not f then
      return
    end
  else
    f = io.input()
  end
  contents = f:read(10000)
  if file then
    f:close()
  end
  if not contents or contents=='' then
    dbg('No settings read')
    return
  -- else
  --   dbg(contents)
  end
  -- remove initial \r and \n characters
  contents = string.gsub(contents, '^[\r\n]*', '');
  -- gmatch chops contents into series of non-line-ending characters
  -- possibly followed by line-ending characters.
  local k, v, vl, vnum
  for l in string.gmatch(contents, '[^\r\n]+[\r\n]*') do
    l =  string.match(l,'[^\r\n]*')
    if not string.match(l, '^#') then
      k, v = string.match(l, '^%s*([^%s]+)%s*=%s*(.*)$')
      if v then v = string.gsub(v,'%s*$', '') end
      -- now handle k and v
      if k == 'pdf_target' then
        -- ignore unless valid option
        if in_list(v, pdf_targets) then
          settings[k] = v
        end
      elseif k == 'pdf_version' then
        -- ignore unless valid option
        if in_list(v, pdf_versions) then
          settings[k] = v
        end
      --[[
      elseif k == 'ignore_hires_bb' then
        vl = string.lower(string.sub(v,1,1))
        if v == 0 or vl == 'n' or vl == 'f' then
          settings.use_hires_bb = true
        elseif v == 1 or vl == 'y' or vl == 't' then
          settings.use_hires_bb = false
        end
      elseif k == 'use_hires_bb' then
        vl = string.lower(string.sub(v,1,1))
        if v == 0 or vl == 'n' or vl == 'f' then
          settings.use_hires_bb = false
        elseif v == 1 or vl == 'y' or vl == 't' then
          settings.use_hires_bb = true
        end
      elseif k == 'bb_spread' then
        vnum = tonumber(v)
        if vnum and vnum >= 0 then
          settings[k] = math.modf(v) -- truncate to integer
        end
        --]]
      elseif k == 'pdftops_prog' then
        if is_miktex then
          settings.pdftops_prog = is_prog(v)
        end -- else ignore
      elseif k == 'ignore_pdftops' then
        vl = string.lower(string.sub(v,1,1))
        if v == 0 or vl == 'n' or vl == 'f' then
          settings.use_pdftops = true
        elseif v == 1 or vl == 'y' or vl == 't' then
          settings.use_pdftops = false
        end
      elseif k == 'use_pdftops' then
        vl = string.lower(string.sub(v,1,1))
        if v == '0' or vl == 'n' or vl == 'f' then
          settings.use_pdftops = false
        elseif v == '1' or vl == 'y' or vl == 't' then
          settings.use_pdftops = true
        end
      -- final three settings not used by epspdf itself but
      -- passed along to epspdftk
      elseif k == 'ps_viewer' then
        settings.ps_viewer = v
      elseif k == 'pdf_viewer' then
        settings.pdf_viewer = v
      elseif k == 'default_dir' then
        settings.default_dir = v
      elseif k == 'default_dir' then
        settings.default_dir = v
      end -- test for k
    end -- not matching ^#
  end -- for
end -- read settings

-- gui: reading and writing settings -----------

function gui(action)
  -- use stdin for reading settings from gui, and stdout for writing
  if action=='config_w' then
    -- called at start of epspdftk
    write_settings() -- to pipe epspdf => epspdftk
    os.exit()
  elseif action=='config_r' then
    read_settings() -- from 'pipe' epspdftk => epspdf
    write_settings(rcfile)
    os.exit()
  else
    from_gui = true
  end
end

-- boundingboxes ---------------------------------------------------

-- [HR]Bb.coords names now same as those of epdf PDFRectangle

Bb = {}
Bb.coords = {'x1', 'y1', 'x2', 'y2'}

function Bb:from_rect(r)
  for _,k in ipairs(self.coords) do
    if not r[k] or type(r[k])~='number' then
      errror('from_rect called with illegal parameters')
    end
    -- sanity check on size
    -- FIXME: this limit is far too high
    if r[k]+.5==r[k] or r[k]-.5==r[k] then
      errror('Bb:from_rect: ' .. r[k] ..' greater than maxint')
    end
    local b = {}
    local eps = 0.000001
    b.x1, b.x2 = math.floor(math.min(r.x1, r.x2) + eps),
        math.ceil(math.max(r.x1, r.x2) - eps)
    b.y1, b.y2 = math.floor(math.min(r.y1, r.y2) + eps),
        math.ceil(math.max(r.y1, r.y2) - eps)
    if b.x1==b.x2 or b.y1==b.y2 then
      errror('from_rect: width or height is zero')
    end
    setmetatable(b, {__index=self})
    return b
  end
end

Bb.bb_pat = '^%s*%%%%BoundingBox:'
Bb.bb_end = '^%s*%%%%BoundingBox:%s*%(%s*atend%s*%)'

function Bb:from_comment(s)
  local p = self.bb_pat..'%s*([-+%d]+)'..string.rep('%s+([-+%d]+)',3)
  local b = {}
  b.x1, b.y1, b.x2, b.y2 = string.match(s, p)
  if not b.y2 then
    errror('Bb.from_comment: illegal boundingbox string ' .. s)
  end
  for _,k in ipairs(self.coords) do
    b[k] = tonumber(b[k])
  end
  return Bb:from_rect(b)
end

--[[ some no-longer-used bbox functions

function Bb:copy ()
  local b = {}
  for _,k in ipairs(self.coords) do b[k] = self[k] end
  setmetatable(b, {__index=self})
end

function Bb:width()
  return self.x2 - self.x1
end

function Bb:height()
  return self.y2 - self.y1
end

function Bb:expand ()
  -- in-place expansion; does not return an object.
  -- any point in preserving non-negativity?
  local i = settings.bb_spread
  if i and i>0 then
    -- if x1~=0 then x1 = x1-1 end
    -- if y1~=0 then y1 = y1-1 end
    self.x1 = self.x1 - 1
    self.y1 = self.y1 - 1
    self.x2 = self.x2 + 1
    self.y2 = self.y2 + 1
  end
end

-- gs handles this now
-- call this via pcall
function Bb:wrapper()
  local fn = mktemp('ps')
  local f = io.open(fn, 'wb')
  f:write(string.format('%%%%BoundingBox: 0 0 %d %d\n',
      self:width(), self:height())
      .. string.format('<< /PageSize [%d %d] >> setpagedevice\n',
         self:width(), self:height())
      .. 'gsave\n'
      .. string.format('%d %d translate\n', -self.x1, -self.y1))
  f:close()
  return fn
end

--]]

function Bb:nonnegative ()
  return self.x1>=0 and self.y1>=0
end

function Bb:comment()
  -- if options.debug then print(debug.traceback()) end
  return string.format('%%%%BoundingBox: %d %d %d %d',
      self.x1, self.y1, self.x2, self.y2)
end

-- hires boundingboxes ---------------------------------------------

HRBb = {}

setmetatable(HRBb, {__index=Bb})

function HRBb:from_rect(r)
  for _,k in ipairs(self.coords) do
    if not r[k] or type(r[k])~='number' then
      errror('from_rect called with illegal parameters')
    end
    -- sanity check on size
    if r[k]+.5==r[k] or r[k]-.5==r[k] then
      errror('HRBb:from_rect: ' .. b[k] ..' greater than maxint')
    end
    local b = {}
    b.x1, b.x2 = math.min(r.x1, r.x2), math.max(r.x1, r.x2)
    b.y1, b.y2 = math.min(r.y1, r.y2), math.max(r.y1, r.y2)
    if b.x1==b.x2 or b.y1==b.y2 then
      errror('from_rect: width or height is zero')
    end
    setmetatable(b, {__index=self})
    return b
  end
end

HRBb.bb_pat = '^%s*%%%%HiResBoundingBox:'
HRBb.bb_end = '^%s*%%%%HiResBoundingBox:%s*%(%s*atend%s*%)%s*$'

function HRBb:from_comment(s)
  -- dbg('hrbb from '..s)
  local p = self.bb_pat..'%s*([-+.%deE]+)'..string.rep('%s+([-+.%deE]+)',3)
  local b = {}
  b.x1, b.y1, b.x2, b.y2 = string.match(s, p)
  if not b.y2 then
    errror('HRBb.from_comment: illegal boundingbox string ' .. s)
  end
  for _,k in ipairs(self.coords) do
    b[k] = tonumber(b[k])
  end
  return HRBb:from_rect(b)
end

function HRBb:comment()
  return string.format('%%%%HiResBoundingBox: %f %f %f %f',
      self.x1, self.y1, self.x2, self.y2)
end

--[[

function HRBb:expand ()
  errror('HRBb:expand not available')
end

-- no longer used: gs handles this
-- call this one also via pcall
function HRBb:wrapper()

  -- local fn = mktemp('ps')
  -- local f = io.open(fn, 'wb')
  -- f.write(string.format('<< /PageSize [%f %f] >> setpagedevice\n',
  --        self.x2 - self.x1, self.y2 - self.y1))
  -- f.write(string.format('gsave\n%f %f translate\n', -self.x1, -self.y1))
  -- f:close()
  -- return fn

  return string.format(
      '<< /PageSize [%f %f] >> setpagedevice gsave %f %f translate',
       self.x2 - self.x1, self.y2 - self.y1, -self.x1, -self.y1)
end

--]]

-- manipulating eps/ps/pdf files -----------------------------------

function identify(path)
  local f = io.open(path, 'rb')
  if not f then
    errror('Failure to open '..path..' for identification')
  end
  local filestart= f:read(23)
  f:close()
  if not filestart or filestart=='' then
    return false
  elseif string.match(filestart,'^\197\208\211\198') then -- c5 d0 d3 c6
    return 'epsPreview'
  elseif string.match(filestart,'^%%!PS%-Adobe%-%d%.%d EPSF%-%d%.%d') then
    return 'eps'
  elseif string.match(filestart,'^%%!PS%-Adobe%-%d%.%d') then
    for _, p in ipairs({'.eps', '.epi', '.epsi', '.epsf'}) do
      if string.sub(string.lower(path), -1-string.len(p),-1) == p then
        return 'eps'
      else
        return 'ps'
      end
    end
    return 'ps'
  elseif string.match(filestart, '^%%PDF') then
    return 'pdf'
  else
    return false
  end
end -- identify

function pdf_props(path)
  local pdfdoc = epdf.open(path)
  if not pdfdoc then
    errror('epdf.open failed on '..path)
  end
  -- if os.type=='windows' then waitasec() end
  local cat = pdfdoc:getCatalog()
  if not cat then
    errror('Cannot open pdf catalog of '..path)
  end
  local pg = cat:getNumPages()
  if not pg then
    errror('Cannot read n. of pages of '..path)
  end
  local maver = pdfdoc:getPDFMajorVersion()
  if not maver then
    errror('Cannot read pdf major version of '..path)
  end
  local miver = pdfdoc:getPDFMinorVersion()
  if not miver then
    errror('Cannot read pdf minor version of '..path)
  end
  if maver > 1 then
    print(path..' has pdf major version \n'..tostring(maver)..
          ' which is unsupported;\n'..
          'Continuing with fingers crossed...')
  end
  return pg, miver, maver
end

function info (infile)
  local intype = identify(infile)
  if not intype then
    print(infile..' has an unsupported filetype.')
  elseif intype~='pdf' then
    print(infile..' has type '..intype..'.')
  else
    local pg, miver, maver = pdf_props(infile)
    print(infile..' has type pdf, version '..tostring(maver)..
        '.'..tostring(miver)..' and has '..tostring(pg)..' pages.')
  end
  os.exit()
end

-- PsPdf object -------------------------------------------------

PsPdf = {}

-- creators

function PsPdf:new(ext)
  -- dbg('PsPdf:new')
  local psp = {}
  setmetatable(psp, {__index = self})
  -- assign temp file
  psp.path = mktemp(string.lower(ext))
  if string.lower(ext)=='pdf' then
    psp.type = 'pdf'
  elseif string.lower(ext)=='eps' then
    psp.type = 'eps'
  elseif string.lower(ext)=='ps' then
    psp.type = 'ps'
  else
    psp.type = false
  end
  if psp.type=='eps' then
    psp.pages = 1
  end
  psp.bb = false
  psp.hrbb = false
  return psp
end -- PsPdf:new

function PsPdf:from_path(path)
  -- dbg('PsPdf:from_path')
  local psp = {}
  setmetatable(psp, {__index = self})
  psp.path = path
  if lfs.isfile(path) then
    -- turn existing file into PsPdf object.
    psp.type = identify(psp.path)
    if psp.type=='pdf' then
      psp.pages, psp.miver, psp.maver = pdf_props(psp.path)
    end
  else
    errror('PsPdf:from_path called with non-existant file '..path)
  end
  if psp.type=='eps' then
    psp.pages = 1
  end
  psp.bb = false
  psp.hrbb = false
  -- calculate when needed
  return psp
end -- PsPdf:from_path

--[===[ getting boundingbox property from file itself --------------

find_bb_simple: use only for eps PsPdf objects we generated
ourselves, so we can assume that the bbox comments are in the header
and the hires bb lies within the lores bb.
Of course the file itself is not rewritten.

--]===]

function PsPdf:find_bb_simple()
  -- dbg('PsPdf:find_bb_simple')
  if self.type~='eps' then
    errror('find_bb_simple called with non-eps file '..self.path)
  end
  self.bb = false
  self.hrbb = false
  local slurp = false
  local f = io.open(self.path, 'rb')
  if f then
    slurp = f:read(bufsize)
    f:close()
  end
  lines = {}
  for l in string.gmatch(slurp, '[^\n\r]+') do
    if string.match(l, Bb.bb_pat) then
      self.bb = Bb:from_comment(l)
    elseif string.match(l, HRBb.bb_pat) then
      self.hrbb = HRBb:from_comment(l)
    elseif self.bb then
      break -- stop looking; we expect hrbb next to bb
    end
    if self.bb and self.hrbb then break end
  end
  if not self.bb then
    errror('No valid boundingbox for generated file' .. self.path)
  end
  return self -- no real need for a return value
end

function PsPdf:bb_from_gs(pg)

  -- dbg('bb_from_gs '..pg)

  if self.type=='ps' then
    errror('bb_from_gs called with ps file '..self.path)
    -- not needed for generic PostScript,
    -- page selection only works with pdf files, so we save ourselves
    -- the trouble of picking the right bbox from a list
  end
  if self.type=='eps' and not self.bb:nonnegative() then
    errror('bb_from_gs called on ' .. self.path ..
        ' which has some negative boundingbox coordinates')
  end
  -- A pdf can also have negative ...Box coordinates, but apparently
  -- for pdf the bbox returned by gs is relative to the lower-left corner.
  -- Anyhow, with pdf it all works out even with negative coordinates.

  -- Since Ghostscript writes the boundingbox comments to stderr,
  -- we need a shell to intercept this output:

  local bb_file = mktemp('dsc')
  local cmdline = gs_prog .. ' ' .. table.concat(gs_options,' ')
  if self.type=='pdf' then
    if not pg then pg=1 end
    cmdline = cmdline .. ' -dFirstPage#' .. tostring(pg) ..
      ' -dLastPage#' .. tostring(pg)
  end
  cmdline = cmdline .. ' -sDEVICE#bbox ' .. self.path .. ' 2>'..bb_file

  -- execute shell command

  local r, cmd
  write_log('os.execute: '..cmdline)
  r = os.execute(cmdline)
  if not r then
    errror('Cannot get fixed boundingbox for '..self.path)
  end

  -- read new bbox from ghostscript output
  -- can we really count on the plain bb coming first?
  -- OTOH, I would rather not introduce unnecessary complexity
  -- still, it may be better to match each line with [HR]Bb_pat

  local bb = false
  local hrbb = false
  local fin = io.open(bb_file, 'r')
  if fin then
    for i=1,10 do -- actually, 2 should suffice
      local l = fin:read("*line")
      if not l then break end
      if string.match(l, Bb.bb_pat) then
        bb = Bb:from_comment(l)
      end
      if string.match(l, HRBb.bb_pat) then
        hrbb = HRBb:from_comment(l)
      end
    end
    fin:close()
  end
  if not bb or not hrbb then
    errror('Cannot get fixed boundingbox for '..self.path)
  end
  return bb, hrbb
end

-- eps_clean: remove some problem features from eps (new file & object)

function PsPdf:eps_clean()

  -- return a PsPdf object referring to a new file
  -- without a preview header and with boundingbox(es) in the header

  local function bytes2num (s, i)
    -- convert substring s[i..i+3] to a number.
    -- by working byte for byte we avoid endian issues
    local n = string.byte(s, i+3)
    for j=2,0,-1 do n = 256*n + string.byte(s, i+j) end
    return n
    -- somehow the explicit expression below didn't work
    -- return ((256 * (256 * (256 * string.byte(s,i+3)) + string.byte(s,i+2))
    --          + string.byte(s,i+1)) + string.byte(s,i))
  end

  -- dbg('PsPdf:eps_clean '..self.path)
  if self.type~='eps' and self.type~='epsPreview' then
    errror('epsclean called with non-eps file ' .. self.path)
  end
  local offset, ps_length = false, false
  local fin, fout
  if self.type=='eps' then
    offset = 0
    ps_length = lfs.attributes(self.path, 'size')
  else
    -- read TOC; see Adobe EPS specification
    -- interpret byte for byte, in case the platform is not little-endian
    fin = io.open(self.path, 'rb')
    if fin then
      local toc = fin:read(12)
      fin:close()
      if toc and string.len(toc)==12 then
        offset = bytes2num(toc, 5)
        ps_length = bytes2num(toc, 9)
      end
    end
    if not offset then
      errror('Could not read preview header of ' .. self.path)
    end
    -- dbg(tostring(offset)..' '..tostring(ps_length))
  end

  -- create the PsPdf object which is to be returned

  local psp
  psp = PsPdf:new('eps')
  -- dbg(psp.path)

  -- read an initial and if necessary a final chunk of the file
  -- to find boundingbox comments.

  local atend = false
  local hr_atend = false
  local slurp -- the read buffer
  local l -- contains current scanned line; split off from slurp
  -- pre_lines: scanned header lines; alternately lines and eols
  local pre_lines = {}
  -- new_offset: offset plus combined length of scanned header lines
  local new_offset = offset
  -- post_lines: scanned trailer lines
  local post_lines = {}
  -- middle_length: ps_length minus scanned header- and and maybe trailer parts
  -- this is the length of file that will be copied wholesale.
  local middle_length
  local i, i_bb, i_hrbb
  local j, j_bb, j_hrbb, j_end
  -- j_end: index of final scanned trailer line
  -- no i_end necessary: for header lines we can use #pre_lines.

  fin = io.open(self.path, 'rb')
  if not fin then errror('Cannot read '..self.path) end
  fin:seek('set', offset)

  -- remaining, unscanned length of input buffer slurp
  local unscanned = math.min(ps_length,bufsize)
  -- dbg('bytes to be read: '..tostring(unscanned))
  slurp = fin:read(unscanned)
  -- dbg('Read from '..self.path..': '..string.len(slurp)..' bytes')

  -- unnecessary:
  psp.bb = nil
  psp.hrbb = nil

  i, i_bb, i_hrbb = 0, false, false
  while unscanned>0 do
    i = i+1
    if string.find(slurp,'[\n\r]')==1 then
      l,slurp = string.match(slurp, '^([\n\r]+)(.*)$')
    else
      l,slurp = string.match(slurp, '^([^\n\r]+)(.*)$')
      if string.match(l, Bb.bb_end) then
        atend = true
        i_bb = i
      elseif string.match(l, Bb.bb_pat) then
        -- dbg(l)
        psp.bb = Bb:from_comment(l)
        -- dbg(psp.bb:comment())
        -- from_comment errors out on failure; no need to check return value
        i_bb = i
      elseif string.match(l, HRBb.bb_end) then
        hr_atend = true
        i_hrbb = i
      elseif string.match(l, HRBb.bb_pat) then
        -- dbg(l)
        psp.hrbb = HRBb:from_comment(l)
        -- dbg(psp.hrbb:comment())
        i_hrbb = i
      end -- bbox line
    end -- eol/non-eol
    pre_lines[i] = l
    unscanned = unscanned - string.len(l)
    if (i_bb and (i_hrbb or (i_bb<(i-1)))) or unscanned<=0 then
      -- condition i_bb<i-1:
      -- We do not want to find the hrbb of an included eps.
      -- Therefore we stop looking for hrbb if it is not next to bb
      -- (with an intervening eol)
      -- Note that the header comments are not necessarily terminated
      -- with a %%EndComments line; see Adobe DSC spec 5001
      break
    end -- deciding whether to stop
  end -- while
  new_offset = offset + string.len(table.concat(pre_lines))
  middle_length = ps_length - string.len(table.concat(pre_lines))

  if atend or hr_atend then
    -- find boundingbox comments, starting from end of postscript
    if ps_length>bufsize then
      fin:seek('set',offset+ps_length-bufsize)
      unscanned = bufsize
      slurp = fin:read(unscanned)
    else
      -- use what is left from old slurp
      unscanned = string.len(slurp)
    end
    j = 1 -- count down from 0
    j_bb, j_hrbb, j_end = false, false, false
    while unscanned>0 do
      j = j - 1
      -- dbg(j)
      if string.find(slurp,'[\n\r]', string.len(slurp)) then
        -- dbg('eol(s)')
        slurp,l = string.match(slurp, '^(.-)([\n\r]+)$')
        -- '-': non-greedy matching
      else
        slurp,l = string.match(slurp, '^(.-)([^\n\r]+)$')
        -- dbg(l)
        if string.match(l, Bb.bb_pat) then
          psp.bb = Bb:from_comment(l)
          j_bb = j
        elseif string.match(l, HRBb.bb_pat) then
          psp.hrbb = HRBb:from_comment(l)
          j_hrbb = j
        end -- bbox line
      end -- eol/non-eol
      post_lines[j] = l
      unscanned = unscanned - string.len(l)
      if (psp.bb and
          (psp.hrbb or not hr_atend or j_bb>(j+1))) or unscanned<=0 then
        -- stop looking
        j_end = j
        break
      end -- deciding whether to stop
    end -- while
    middle_length = middle_length -
      string.len(table.concat(post_lines, '', j_end, 0))
  end --if atend
  fin:close()
  -- fix boundingbox lines
  if atend and j_bb then
    -- pre_lines[i_bb] = post_lines[j_bb]
    pre_lines[i_bb] = psp.bb:comment() -- WHY DOESNT THIS WORK ????
    post_lines[j_bb] = ''
    post_lines[j_bb+1] = ''
  end
  if hr_atend and j_hrbb then
    -- dbg(psp.hrbb:comment())
    -- pre_lines[i_hrbb] = post_lines[j_hrbb]
    pre_lines[i_hrbb] = psp.hrbb:comment()
    post_lines[j_hrbb] = ''
    post_lines[j_hrbb+1] = ''
  end
  -- create cleaned eps file
  fout = io.open(psp.path, 'wb')
  if not fout then errror('Cannot create new file '..psp.path) end
  fout:write(table.concat(pre_lines))
  fout:close()
  slice_file(self.path, psp.path, middle_length, new_offset, 'ab')
  fout = io.open(psp.path, 'ab')
  fout:write(table.concat(post_lines, '', j_end, 0))
  fout:close()
  return psp
end -- eps_clean

-- tight boundingbox (new file & object)

function PsPdf:eps_crop()

  -- not a proper conversion, although
  -- we use the Ghostscript bbox device for a tight boundingbox.
  -- We use both the regular and the hires boundingbox from gs.
  -- The eps should already have been cleaned up by eps_clean,
  -- and the current boundingbox should not contain negative coordinates,
  -- otherwise the bbox output device may give incorrect results.
  -- Only the boundingbox in the eps is rewritten.

  -- dbg('PsPdf:eps_crop '..self.path)
  if self.type~='eps' then
    errror('eps_crop called with non-eps file ' .. self.path)
  end

  -- create the PsPdf object which is to be returned

  local psp = PsPdf:new('eps')

  -- read new bbox from ghostscript output

  psp.bb, psp.hrbb = self:bb_from_gs()

  -- rewrite header with new boundingboxes

  local slurp -- the read buffer
  local l -- contains current scanned line; split off from slurp
  -- pre_lines: scanned header lines; alternately lines and eols
  local pre_lines = {}
  -- offset: combined length of scanned header lines
  local offset = 0
  local ps_length = lfs.attributes(self.path, 'size')
  local i, i_bb, i_hrbb

  fin = io.open(self.path, 'rb')
  if not fin then errror('Cannot read '..self.path) end

  -- remaining, unscanned length of input buffer slurp
  local unscanned = math.min(ps_length,bufsize)
  -- dbg('bytes to be read: '..tostring(unscanned))
  slurp = fin:read(unscanned)
  -- dbg('Read from '..self.path..': '..string.len(slurp)..' bytes')
  i, i_bb, i_hrbb = 0, false, false
  while unscanned>0 do
    i = i+1
    if string.find(slurp,'[\n\r]')==1 then
      l,slurp = string.match(slurp, '^([\n\r]+)(.*)$')
    else
      l,slurp = string.match(slurp, '^([^\n\r]+)(.*)$')
      if string.match(l, Bb.bb_pat) then
        i_bb = i
      elseif string.match(l, HRBb.bb_pat) then
        i_hrbb = i
      end -- bbox line
    end -- eol/non-eol
    pre_lines[i] = l
    unscanned = unscanned - string.len(l)
    if (i_bb and (i_hrbb or (i_bb<(i-1)))) or unscanned<=0 then
      break
    end
  end -- while
  fin:close()
  offset = string.len(table.concat(pre_lines))

  if i_hrbb then
    pre_lines[i_bb] = psp.bb:comment()
    pre_lines[i_hrbb] = psp.hrbb:comment()
  else
    -- jam both bbox comments into one slot, with an intervening eol.
    -- for the sake of conformity, we copy an existing eol.
    pre_lines[i_bb] = psp.bb:comment() .. pre_lines[i_bb-1] ..
        psp.hrbb:comment()
  end

  -- write a new eps file

  fout = io.open(psp.path, 'wb')
  if not fout then errror('Cannot write new file '.. psp.path) end
  fout:write(table.concat(pre_lines))
  fout:close()
  slice_file(self.path, psp.path,
      lfs.attributes(self.path,'size') - offset, offset, 'ab')
  options.bbox = false
  -- dbg('eps_crop from '..self.path..' to '..psp.path)
  return psp
end -- eps_crop

--[===[ real conversions involving a single call of gs, pdftops or texlua

Each conversion fullfills all options that it can: gray, bbox and
page. gray when converting to pdf, bbox when converting from eps or
from pdf to pdf and page when converting from pdf. It then sets the
fullfilled option(s) to false.

We like to preserve fonts as fonts. gs does this when generating
pdf, but may fail for fonts such as cid and large truetype when
generating PostScript. In such cases, pdftops may succeed. However,
it seems that if the page contains an element that does not cleanly
convert, pdftops simply rasterizes the entire page, and that this
choice is made per page.

--]===]

-- TODO: multiple pages?
-- (means additional parameter checking)

-- Converting from pdf to pdf using luatex; no grayscaling

function PsPdf:pdf_crop()

  -- options to be fulfilled: page, boundingbox
  -- only called directly.
  -- embeds the pdf with crop parameters into a new (lua)tex document
  -- dbg('PsPdf:pdf_crop '..self.path)
  if not (options.bbox or options.page) then
    return self
  end
  if options.page and options.page > self.pages then
    errror('PsPdf:pdf_crop called with non-existent page '.. options.page)
  end
  local pg = options.page or 1
  local bb, hrbb, pgbox, pgboxname
  do
    local pdoc, pcat, ppage
    -- we already have the pages, miver and maver properties
    -- but need properties of the desired page as well
    pdoc = epdf.open(self.path)
    if not pdoc then
      errror('Epdf: cannot open '..self.path)
    end
    -- dbg('about to get catalog')
    pcat = pdoc:getCatalog()
    if not pcat then
      errror('Cannot open catalog of '..self.path)
    end
    -- dbg('got catalog')
    ppage = pcat:getPage(pg)
    if not ppage then
      errror('Epdf: cannot open page object '..tostring(pg)..' of '..self.path)
    end
    pgboxname = 'trimbox'
    pgbox = ppage:getTrimBox()
    if not pgbox then
      pgboxname = 'cropbox'
      pgbox = ppage:getCropBox()
    end
    if not pgbox then
      pgboxname = 'mediabox'
      pgbox = ppage:getMediaBox()
    end
    -- normalization and further checks, including for non-nil,
    -- by Bb:from_rect, which errors out on failures
    pgbox = HRBb:from_rect(pgbox)
  end
  if options.bbox then
    bb, hrbb = self:bb_from_gs(pg)
  else
    hrbb = pgbox
  end

  -- luatex on searchpath
  local luatex_prog = 'luatex'

  -- write TeX file which includes cropped pdf page
  -- adapted from Heiko Oberdiek's pdfcrop utility.
  -- the table `pieces' will contain the component strings for the tex source
  -- first, for texlua <= 0.81
  local pieces = {}
  if status.luatex_version <= 80 then
    pieces[1] = '\\pdfoutput=1\n'
  else
    pieces[1] = [[
\edef\pdfminorversion {\pdfvariable minorversion}
\edef\pdfcompresslevel {\pdfvariable compresslevel}
\edef\pdfobjcompresslevel {\pdfvariable objcompresslevel}
\edef\pdfdecimaldigits {\pdfvariable decimaldigits}
\edef\pdfhorigin {\pdfvariable horigin}
\edef\pdfvorigin {\pdfvariable vorigin}
\let\pdfpagewidth\pagewidth
\let\pdfpageheight\pageheight
\let\pdfximage\saveimageresource
\let\pdfrefximage\useimageresource
\let\pdflastximage\lastsavedimageresourceindex

\outputmode=1
]]
  end
  if self.maver > 1 then
    pieces[2] = '\\pdfminorversion=9\n'
  else
    pieces[2] = '\\pdfminorversion=' .. self.miver .. '\n'
  end
  if self.maver > 1 or self.miver > 4 then
    pieces[3] = [[
\pdfcompresslevel=9
\pdfobjcompresslevel=2
\pdfdecimaldigits=4
]]
  else
    pieces[3] = [[
\pdfcompresslevel=9
\pdfobjcompresslevel=0
\pdfdecimaldigits=4
]]
  end
  pieces[4] = [[
\def\page #1 [#2 #3 #4 #5]{%
  \count0=#1\relax
  \setbox0=\hbox{%
    \pdfximage page #1 mediabox{]]
  pieces[5] = self.path
  pieces[6] = [[}%
    \pdfrefximage\pdflastximage
  }%
  \pdfhorigin=-#2bp\relax
  \pdfvorigin=#3bp\relax
  \pagewidth=#4bp\relax
  \advance\pagewidth by -#2bp\relax
  \pageheight=#5bp\relax
  \advance\pageheight by -#3bp\relax
  \ht0=\pageheight
  \shipout\box0\relax
}
]]
  pieces[7] = string.format([[
\page %d [%f %f %f %f]
\csname @@end\endcsname
\end
]],
  options.page or 1, hrbb.x1, hrbb.y1, hrbb.x2, hrbb.y2)

  local textemp = mktemp('tex') -- this also took care of pdf:
  local pdftemp = string.gsub(textemp, 'tex$', 'pdf')
  -- if os.type=='windows' then waitasec() end
  local f = io.open(textemp, 'w')
  -- if os.type=='windows' then waitasec() end
  f:write(table.concat(pieces, ''))
  f:close()
  local cmd, res, psp
  if os.type=='unix' then
    cmd = {luatex_prog, '--safer', '--no-shell-escape', textemp}
    log_cmd(cmd)
    res = os.spawn(cmd)
  else
    cmd = luatex_prog..' --safer --no-shell-escape '..textemp
    log_cmd({cmd})
    -- os.execute('timeout /t 1 /nobreak >nul')
    res = os.execute(cmd)
  end
  if res and res==0 and lfs.attributes(pdftemp, 'size')>0 then
    psp = PsPdf:from_path(pdftemp)
    return psp
  else
    errror('pdf_crop failed on '..self.path)
  end
end

function PsPdf:eps_to_pdf()

  -- option to be fulfilled: gray
  -- set target and pdf version if applicable
  -- dbg('PsPdf:eps_to_pdf '..self.path)
  if self.type~='eps' then
    errror('PsPdf:eps_to_pdf called for non-eps file '.. self.path)
  end
  local cmd
  if options.bbox and self.bb:nonnegative() then
    self = self:eps_crop() -- this sets options.bbox to false
  end
  cmd = tab_combine({{gs_prog}, gs_options, pdf_options})
  -- dbg(table.concat(cmd,' '))
  if options.gray then
    cmd = tab_combine({cmd, gray_options})
  -- dbg(table.concat(cmd,' '))
    options.gray = false
  end
  table.insert(cmd, '-dEPSCrop') -- always hires bb
  -- dbg(table.concat(cmd,' '))
  local psp = PsPdf:new('pdf')
  table.insert(cmd, '-sOutputFile#'..psp.path)
  -- dbg(table.concat(cmd,' '))
  cmd = tab_combine({cmd, pdf_tail_options, {self.path}})
  -- dbg(table.concat(cmd,' '))
  log_cmd(cmd)
  local res = os.spawn(cmd)
  if res and res==0 and lfs.attributes(psp.path, 'size')>0 then
    psp.pages, psp.miver, psp.maver = pdf_props(psp.path)
    return psp
  else
    errror('eps_to_pdf failed on '..self.path)
  end
end -- eps_to_pdf

-- Converting from pdf to pdf with grayscaling and/or page selection

function PsPdf:pdf_to_pdf()

  -- option to be fulfilled: gray and optionally page.
  -- do not call this just for page selection because
  -- pdf_crop can do this in a less invasive manner
  -- dbg('PsPdf:pdf_to_pdf '..self.path)
  if self.type~='pdf' then
    errror('PsPdf:pdf_to_pdf called for non-pdf file '.. self.path)
  end
  local cmd
  if options.page and options.page > self.pages then
    errror('PsPdf:pdf_to_pdf called with non-existent page '.. options.page)
  end
  cmd = tab_combine({{gs_prog}, gs_options, pdf_options})
  -- dbg(table.concat(cmd,' '))
  if options.gray then
    cmd = tab_combine({cmd, gray_options})
    -- dbg(table.concat(cmd,' '))
    options.gray = false
  end
  if options.page then
    table.insert(cmd, '-dFirstPage#'..tostring(options.page))
    table.insert(cmd, '-dLastPage#'..tostring(options.page))
    -- dbg(table.concat(cmd,' '))
    options.page = false
  end
  local psp = PsPdf:new('pdf')
  table.insert(cmd, '-sOutputFile#'..psp.path)
  cmd = tab_combine({cmd, pdf_tail_options})
  -- dbg(table.concat(cmd,' '))
  table.insert(cmd, self.path)
  -- dbg(table.concat(cmd,' '))
  log_cmd(cmd)
  local res = os.spawn(cmd)
  if res and res==0 and lfs.attributes(psp.path, 'size')>0 then
    psp.pages, psp.miver, psp.maver = pdf_props(psp.path)
    return psp
  else
    errror('pdf_to_pdf failed on '..self.path)
  end
end -- pdf_to_pdf

function PsPdf:pdf_to_eps()

  -- options to be fulfilled: bbox and page
  -- dbg(tostring(settings.pdftops_prog))
  -- dbg('pdf_to_eps '..self.path)
  local psp = PsPdf:new('eps')
  local cmd, res
  local page = false
  if self.pages > 1 then
    if options.page then
      page = options.page
      if page > self.pages then
        errror('PsPdf:pdf_to_eps called with non-existant page '..
            tostring(page))
      end
    else
      page = 1
    end
    page = tostring(page)
  end -- self.pages > 1
  if pdftops then
    if page then
      cmd = tab_combine({{pdftops}, ps_options,
        {'-f', page, '-l', page,
         '-eps', self.path, psp.path}})
    else
      cmd = tab_combine({{pdftops}, ps_options,
        {'-eps', self.path, psp.path}})
    end
    options.page = false
    log_cmd(cmd)
    if os.type=='windows' then
      -- suppress console output of 'No display font for...' messages,
      -- which are usually harmless and for which I know no easy fix
      -- pdftops -q does not do the trick on Windows,
      -- and redirection to logfile gives access denied under miktex
      -- res = os.spawn({'cmd', '/c', table.concat(cmd, ' ')..' 2>>'..log_bsl})
      res = os.execute(table.concat(cmd, ' ')..' 2>nul')
    else
      res = os.spawn(cmd)
    end
    if res and res==0 and lfs.attributes(psp.path, 'size')>0 then
      psp.pages = 1
    else
      errror('pdf_to_eps failed on '..self.path)
    end
    -- fix for incorrect DSC header produced by some versions of pdftops:
    -- if necessary, change line `% Produced by ...' into `%%Produced by ...'
    -- this is usually the second line.
    -- otherwise the DSC header would be terminated before the bbox comment.
    -- this problem exists with pdftops from TL2011/w32.
    local slurp -- input buffer
    local fin = io.open(psp.path, 'rb')
    if not fin then errror('Cannot read '..psp.path) end

    -- remaining, unscanned length of input buffer slurp
    local unscanned = math.min(lfs.attributes(psp.path, 'size'),bufsize)
    slurp = fin:read(unscanned)
    local i, i_bb = 0, false
    local needs_fixing = false
    local pre_lines = {}
    local offset = 0
    while unscanned>0 do
      i = i+1
      if string.find(slurp,'[\n\r]')==1 then
        l,slurp = string.match(slurp, '^([\n\r]+)(.*)$')
      else
        l,slurp = string.match(slurp, '^([^\n\r]+)(.*)$')
        if string.match(l, Bb.bb_pat) then
          -- bbox line
          i_bb = i
        elseif string.match(l, '^%%%s') then -- `%' is escape char: doubled
          -- %X with X printable would be ok
          needs_fixing = true
          -- fix rightaway
          l = string.gsub(l, '^%%%s', '%%%%') -- same length
        end
      end -- eol/non-eol
      pre_lines[i] = l
      unscanned = unscanned - string.len(l)
      offset = offset + string.len(l)
      if i_bb then break end
    end -- while
    fin:close()
    if needs_fixing then
      -- write a new eps file
      local newfile = mktemp('eps')
      fout = io.open(newfile, 'wb')
      if not fout then errror('Cannot write new file '.. newfile) end
      fout:write(table.concat(pre_lines))
      fout:close()
      -- dbg('fixing '..psp.path..' to '..newfile)
      slice_file(psp.path, newfile,
        lfs.attributes(psp.path,'size') - offset, offset, 'ab')
      psp.path = newfile
    end -- needs_fixing
  else -- use ghostscript
    local epsdev = epsdevice()
    if not epsdev then
      errror('Conversion to eps not supported by this ghostscript')
    end
    cmd = tab_combine({{gs_prog}, gs_options,
      {'-sDEVICE#'..epsdev, '-dHaveTrueTypes=true', '-dLanguageLevel#3'}})
    -- the restrictions on eps files are apparently
    -- incompatible with grayscaling
    if options.page then
      table.insert(cmd, '-dFirstPage='..options.page)
      table.insert(cmd, '-dLastPage='..options.page)
    end
    table.insert(cmd, '-sOutputFile='..psp.path)
    table.insert(cmd, self.path)
    options.page = false
    log_cmd(cmd)
    res = os.spawn(cmd)
    if res and res==0 and lfs.attributes(psp.path, 'size')>0 then
      psp.pages = 1
    else
      errror('pdf_to_eps failed on '..self.path)
    end
  end -- use ghostscript
  psp:find_bb_simple()
  if options.bbox then psp = psp:eps_crop() end
  return psp

end -- pdf_to_eps

function PsPdf:ps_to_pdf()

  -- options to be fulfilled: gray
  -- dbg('PsPdf:ps_to_pdf '..self.path)
  if self.type~='ps' then
    errror('PsPdf:ps_to_pdf called for non-ps file '.. self.path)
  end
  local cmd
  cmd = tab_combine({{gs_prog}, gs_options, pdf_options})
  if options.gray then
    cmd = tab_combine({cmd, gray_options})
    options.gray = false
  end
  local psp = PsPdf:new('pdf')
  table.insert(cmd, '-sOutputFile#'..psp.path)
  cmd = tab_combine({cmd, pdf_tail_options})
  table.insert(cmd, self.path)
  log_cmd(cmd)
  local res = os.spawn(cmd)
  if res and res==0 and lfs.attributes(psp.path, 'size')>0 then
    psp.pages, psp.miver, psp.maver = pdf_props(psp.path)
    return psp
  else
    errror('ps_to_pdf failed on '..self.path)
  end

end -- PsPdf:ps_to_pdf

function PsPdf:pdf_to_ps()

  -- options to be fulfilled: page and, if not using pdftops, also gray
  -- dbg('PsPdf:pdf_to_ps '..self.path)
  local psp = PsPdf:new('ps')
  local page = false
  if self.pages>1 then
    if options.page and options.page > self.pages then
      errror('PsPdf:pdf_to_ps called with non-existant page '.. options.page)
    elseif options.page then
      page = tostring(options.page)
      psp.pages = 1
    end
  else
    psp.pages = self.pages
  end
  local cmd, res
  if pdftops then
    cmd = tab_combine({{pdftops}, ps_options})
    if page then
      cmd = tab_combine({cmd, {'-f', page, '-l', page}})
    end
    cmd = tab_combine({cmd, {'-paper', 'match', self.path, psp.path}})
  else -- use ghostscript
    cmd = tab_combine({{gs_prog}, gs_options,
        {'-sDEVICE#ps2write', '-dHaveTrueTypes=true', '-dLanguageLevel#3'}})
    if options.gray then
      cmd = tab_combine({cmd, gray_options})
    -- dbg(table.concat(cmd,' '))
      options.gray = false
    end
    if page then
      cmd = tab_combine({cmd, {'-dFirstPage#'..page, '-dLastPage#'..page}})
    end
    table.insert(cmd, '-sOutputFile#'..psp.path)
    -- table.insert(cmd, '-f')
    table.insert(cmd, self.path)
  end
  options.page = false
  log_cmd(cmd)
  if os.type=='windows' and pdftops then
    -- suppress console output of 'No display font for...' messages,
    -- which are usually harmless and for which I know no easy fix
    -- pdftops -q does not do the trick on Windows,
    -- and redirection to logfile gives access denied under miktex
    -- res = os.spawn({'cmd', '/c', table.concat(cmd, ' ')..' 2>>'..log_bsl})
    res = os.execute(table.concat(cmd, ' ')..' 2>nul')
  else
    res = os.spawn(cmd)
  end
  if res and res==0 and lfs.attributes(psp.path, 'size')>0 then
    return psp
  else
    errror('pdf_to_ps failed on '..self.path)
  end
end -- PsPdf:pdf_to_ps

function PsPdf:any_to_any()

  -- weed out nonsense options

  -- dbg('PsPdf:any_to_any '..self.path)
  if options.type=='ps' then
    options.bbox = false
    -- dbg('Ignoring bbox option for ps output')
  end
  if options.bbox and not options.page then
    options.page = 1
    -- dbg('Selecting page 1 for bbox')
  end
  if self.pages==1 then
    options.page = false
    -- dbg('dropping page selection; source is already a 1-page document')
  end
  -- for _,o in ipairs({'page', 'gray', 'bbox'}) do
  --   -- if options[o] then dbg('Do option '..o) end
  -- end

  -- `distiller' settings depend on whether final output is pdf
  -- '.setpdfwrite' is just some optimization option for ghostscript
  if options.type=='pdf' then
    if settings.pdf_version~='default' then
      table.insert(pdf_options, '-dCompatibilityLevel#'..settings.pdf_version)
    end
    -- below, consider adding <</NeverEmbed [/Times-Roman /TimesBold ...]>>
    if settings.pdf_target=='screen' or settings.pdf_target=='ebook' then
      pdf_tailoptions = {'-c', '.setpdfwrite', '-f'}
      -- -f ensures that the input filename is not added to the -c string
    else
      pdf_tailoptions = {
          '-c', '.setpdfwrite <</NeverEmbed [ ] >> setdistillerparams', '-f'}
    end
  else
    pdf_tailoptions = {
        '-c', '.setpdfwrite <</NeverEmbed [ ] >> setdistillerparams', '-f'}
  end

  if options.type=='pdf' then
    table.insert(pdf_options, '-dPDFSETTINGS#/'..settings.pdf_target)
    if settings.pdf_version~='default' then
      table.insert(pdf_options, '-dCompatibilityLevel#'..settings.pdf_version)
    end
  else
    table.insert(pdf_options, '-dPDFSETTINGS#/default')
  end

  --[[
  each single-step conversion takes care of options it can handle
  and sets those options to false.
  for boundingboxes, eps_crop is either called explicitly
  or called implicitly by another converter.
  pdf_crop is always called explicitly and always as the last step

  all calls to external programs work on temporary files
  in the then-current temporary directory, with a simple generated
  filename. So no need to quote names of input- and output filenames.
  --]]

  local psp = self
  local newfile

  if psp.type=='eps' or psp.type=='epsPreview' then
    -- As a side effect of eps_clean, the modified source file is copied
    -- to the temp subdirectory.
    psp = psp:eps_clean()
    if options.bbox and psp.bb:nonnegative() then
      psp = psp:eps_crop()
    end
    if options.type=='eps' then
      if options.gray or options.bbox then
        -- bbox: eps_crop was apparently not applicable: pdf roundtrip
        psp = psp:eps_to_pdf():pdf_to_eps()
      end
    elseif options.type=='pdf' then
      psp = psp:eps_to_pdf()
      if options.bbox then
        psp = psp:pdf_crop()
      end
    elseif options.type=='ps' then
      psp = psp:eps_to_pdf():pdf_to_ps()
    end
    return psp

  elseif psp.type=='ps' then
    -- preliminary:
    -- copy infile to a file in the temp directory, needed for gs -dSAFER
    newfile = mktemp(psp.type)
    slice_file(psp.path, newfile)
    -- dbg(psp.path..' copied to '..newfile..' in '..lfs.currentdir())
    psp.path = newfile

    -- actual conversion
    if options.type=='eps' then
      return psp:ps_to_pdf():pdf_to_eps()
    elseif options.type=='pdf' then
      if options.bbox or options.page then
        return psp:ps_to_pdf():pdf_crop()
      else
        return psp:ps_to_pdf()
      end
    elseif options.type=='ps' then
      if options.gray or options.page then
        return psp:ps_to_pdf():pdf_to_ps()
      else
        return psp -- no conversion necessary
      end
    end -- pdf => ps

  elseif psp.type=='pdf' then
    -- preliminary:
    -- copy infile to a file in the temp directory, for gs -dSAFER
    newfile = mktemp(psp.type)
    slice_file(psp.path, newfile)
    -- dbg(psp.path..' copied to '..newfile..' in '..lfs.currentdir())
    psp.path = newfile

    -- actual conversion
    if options.type=='eps' then
      if options.gray then
        -- one-step grayscaling available for gs/ps but not for gs/eps
        return psp:pdf_to_pdf():pdf_to_eps()
      else
        return psp:pdf_to_eps()
      end
    elseif options.type=='pdf' then
      -- pdf_crop can take care of bbox and page,
      -- but not of gray and not of target use or pdf version
      do
        local need_gs = false
        -- compare actual and required versions,
        -- allowing for rounding differences
        if settings.pdf_version~='default' and
            (psp.maver+0.1*psp.miver)>tonumber(settings.pdf_version)-0.01 then
          need_gs = true
        end
        if settings.pdf_target~='default' then
          need_gs = true
        end
        if options.gray then
          need_gs = true
        end
        local need_crop = false
        if options.bbox then
          need_crop = true
        end
        if (not need_gs) and options.page then
          need_crop = true
        end
        if need_gs then
          psp = psp:pdf_to_pdf()
        end
        if need_crop or (psp.pages>1 and options.page) then
          psp = psp:pdf_crop()
        end
        return psp
      end
    elseif options.type=='ps' then
      if options.gray and pdftops then
        return psp:pdf_to_pdf():pdf_to_ps()
      else
        return psp:pdf_to_ps()
      end
    end -- pdf => ps
  end -- psp.type=='ps'|'pdf'
end -- any_to_any

-- system-dependent initialization -----------------------------------

-- current directory, at program start
cwd = lfs.currentdir()
if os.type == 'windows' then cwd = string.gsub(cwd, '\\', '/') end

-- child searchpath initially set to parent searchpath
-- childpath = os.getenv('PATH')

-- prepend (lua)tex directory to searchpath, if not already there
maybe_add_path(os.selfdir, false)

-- Windows: miktex, TL or neither. is_miktex, is_tl_w32, auto_psp
-- no support yet for separate ghostscript
is_miktex = false
is_tl_w32 = false
auto_psp = true -- only false for old miktex without included pdftops

if os.type == 'windows' then
  if string.find (string.lower(kpse.version()), 'miktex') then
    is_miktex = true
  else
    local rt = string.gsub(os.selfdir,'[\\/][^\\/]+[\\/][^\\/]+$', '')
    if not rt then
      errror('Unrecognized TeX directory structure', 0)
    elseif lfs.isfile(rt..'/release-texlive.txt') then
      --[[
      -- TL version is easy to determine but is not needed
      local fin = io:open(rt..'release-texlive.txt', 'r')
      if fin then
        local l = fin:read('*line')
        tl_ver = string.match(l, 'version%s+(%d+)$')
        if tl_ver then tl_ver = tonumber(tl_ver) end
      end -- if fin
      --]]
      is_tl_w32 = true
    else
      errror('Not MikTeX and no file ' .. rt ..
          '/release-texlive.txt; TeX installation not supported.', 0)
    end -- if isfile
  end -- if not miktex
  -- recent miktex and any windows tl include pdftops
  if not lfs.isfile(string.gsub(os.selfdir, '\\', '/') .. '/pdftops.exe') then
    auto_psp = false
  end
end -- if windows

-- without Ghostscript we are dead in the water.
-- TL/w32: add to searchpath
gs_prog = false
do
  local rt=''
  if os.type == 'unix' then
    if find_on_path('gs') then
      gs_prog = 'gs'
    else
      error('No ghostscript on searchpath!', 0)
    end
  elseif is_miktex then
    gs_prog = 'mgs.exe'
    -- neither MiKTeX's nor TL's ghostscript need GS_LIB to be set
  elseif is_tl_w32 then
    -- windows/TeX Live
    -- grandparent of texlua.exe directory .. ...
    rt = string.gsub(os.selfdir,'[\\/][^\\/]+[\\/][^\\/]+$', '')
        ..'/tlpkg/tlgs'
    maybe_add_path(rt..'/bin', false)
    gs_prog = 'gswin32c.exe'
    --[[ problems with (at least) grayscaling
    gs_prog = 'rungs.exe'
    --]]
  else
    errror('Only TeX Live and MikTeX supported!', 0)
  end
end -- do

-- directory for configuration and log
epsdir = ''
if os.type == 'windows' then
  epsdir = fw(ep_shortname(os.getenv('APPDATA'))) .. '/epspdf'
else
  epsdir = os.getenv('HOME')..'/.epspdf'
end
-- dbg('epsdir: '..epsdir)
rcfile = epsdir .. '/config'
logfile = epsdir .. '/epspdf.log'

-- create epsdir if necessary
if lfs.isfile(epsdir) then
  error('Cannot continue; epspdf directory ' .. epsdir .. ' is a file')
elseif not lfs.isdir(epsdir) then
  if not lfs.mkdir(epsdir) then
    error('Failed to create epspdf directory ' .. epsdir)
  end
end

-- start logging ---------------------------------

-- log rotate if logfile too big
if lfs.attributes(logfile) and lfs.attributes(logfile).size > 100000 then
  local oldlog = logfile .. '.old'
  if lfs.attributes(oldlog) then
    if os.remove(oldlog) then os.rename(logfile,oldlog) end
  elseif lfs.attributes(logfile) then do
    -- separate epsdir runs with empty lines
    print_log('\n\nNew run')
  end end -- do elseif
end -- if lfs...logfile

write_log('epspdf '..table.concat(arg, ' '))

--[[ some debug output

dbg ('os is ' .. os.type .. ' and ' .. os.name)
dbg ('texlua in ' .. os.selfdir)
dbg('Ghostscript: ' .. gs_prog)
--]]

--[[

settings, initial values

The values in the settings array have lowest priority - lower than
autodetect and command-line options.  We go for false rather than
undefined, because this results in an actual settings entry.
We ignore illegal settings in the config file.

--]]

pdf_targets = {'screen', 'ebook', 'printer', 'prepress', 'default'}
pdf_versions = {'1.2', '1.3', '1.4', 'default'}

settings = {}
descriptions = {}

settings.pdf_target = 'default'
descriptions.pdf_target = 'One of ' .. join(pdf_targets, ', ', ' or ')

settings.pdf_version = 'default'
descriptions.pdf_version = 'One of ' .. join(pdf_versions, ', ', ' or ')

--[[
-- is bb_spread still a useful setting?
-- look at gs options wrt boundingbox
-- settings.bb_spread = 1
-- descriptions.bb_spread = 'Safety margin in points for (low-res) boundingbox'

settings.use_hires_bb = false
-- descriptions.use_hires_bb = 'Use high-resolution boundingbox if available'
-- Ignored; hires bb always used
--]]

-- because pdftops_prog is sometimes configurable, it is stored in settings.
-- it will not be used for TeX Live and only be read and written on Windows.

settings.pdftops_prog = false
descriptions.pdftops_prog =
  'Full path to pdftops.exe (not used if TeX bin dir contains pdftops)'

settings.use_pdftops = true
descriptions.use_pdftops = 'Use pdftops if available'

-- epspdf stores ps- and pdf viewer settings on behalf of the gui interface
-- but does not use them itself.
-- They won't be used at all under osx or windows.

settings.ps_viewer = false
descriptions.ps_viewer =
  'Epspdftk: viewer for PostScript files; not used on Windows or OS X'

settings.pdf_viewer = false
descriptions.pdf_viewer =
  'Epspdftk: viewer for pdf files; not used on Windows or OS X'

-- default_dir, which is used on all platforms, is only for the gui.

if os.type == 'windows' then
  settings.default_dir =
      string.gsub(ep_shortname(os.getenv('USERPROFILE')), '\\', '/')
else
  settings.default_dir = os.getenv('HOME')
end
descriptions.default_dir =
  'Epspdftk: initial directory; ignored by epspdf itself'

-- options -------------------------------------

-- besides settings, which can be saved, we also use options which are not.
-- these are mostly conversion options.

options = {}
options.page = false
options.gray = false
options.bbox = false
options.debug = false
options.type = false -- implied via output filename on command line

-- command-line fragments for conversions --------------------

-- We could make these `class attributes' for PsPdf but to what purpose?
-- For Windows shell commands, we need to substitute `#' for `='
-- when invoking Ghostscript. For simplicity, we do this across the board.

gs_options = {'-q', '-dNOPAUSE', '-dBATCH', '-P-', '-dSAFER'}

-- may add custom options later

pdf_options = {'-sDEVICE#pdfwrite'} -- '-dUseCIEColor' causes serious slowdown
-- options for final conversion to pdf;
-- will be completed after reading settings and options
pdf_tail_options = {'-c', '.setpdfwrite', '-f'}
gray_options = {'-dProcessColorModel#/DeviceGray',
  '-sColorConversionStrategy#Gray'}

pdftops = false
-- gets a value only if we are going to use pdftops

ps_options = {'-level3'}
-- may add custom options later

-- `main program' inside scope-creating block ----------------------

do -- main program

  local infile = false
  local in_dir = false -- directory of infile
  local outfile = false
  local out_dir = false -- directory of outfile

  -- dbg('\nSettings are:\n')
  for k,v in pairs(settings) do dbg(k .. ' = ' .. tostring(v)) end

  do -- Handle settings and command-line inside nested scope --------------

    read_settings(rcfile)

    -- dbg('Defining cmdline options')
    local opts = {}

    opts.page = {
      type = 'string', val = nil,
      forms = {'-p', '--page', '--pagenumber'},
      placeholder = 'PNUM',
      negforms = nil,
      help = 'Page number; must be a positive integer'
    }

    opts.gray = {
      type = 'boolean', val = nil,
      forms = {'-g', '--grey', '--gray', '-G', '--GREY', '--GRAY'},
      negforms = nil,
      help = 'Convert to grayscale'
    }

    opts.bbox = {
      type = 'boolean', val = nil,
      forms = {'-b', '--bbox', '--BoundingBox'},
      negforms = nil,
      help = 'Compute tight boundingbox'
    }

    ---[[ ignored; included for backward compatibility
    opts.use_hires_bb = {
      type = 'boolean', val = nil,
      forms = {'-r', '--hires'},
      negforms = {'-n', '--no-hires'},
    }

    opts.custom = {
      type = 'string', val = nil,
      forms = {'-C', '--custom', '-P', '--psoptions'},
      negforms = nil
    }
    --]]

    opts.pdf_target = {
      type = 'string', val = nil,
      forms = {'-T', '--target'},
      placeholder = 'TARGET',
      negforms = nil,
      help = descriptions.pdf_target
    }
    opts.pdf_version = {
      type = 'string', val = nil,
      forms = {'-N', '--pdfversion'},
      placeholder = 'VERSION',
      negforms = nil,
      help = descriptions.pdf_version
    }

    if os.type=='windows' and not auto_psp then
      opts.pdftops_prog = {
        type = 'string', val = nil,
        forms = {'--pdftops'},
        placeholder = 'PATH',
        negforms = nil,
        help = descriptions.pdftops_prog
      }
    end

    opts.use_pdftops = {
      type = 'boolean', val = nil,
      forms = {'-U'},
      negforms = {'-I'},
      help = descriptions.use_pdftops
    }

    opts.info = {
      type = 'boolean', val = nil,
      forms = {'-i', '--info'},
      negforms = nil,
      help = 'Info: display detected filetype and exit'
    }

    opts.help = {
      type = 'boolean', val = nil,
      forms = {'-h', '--help'},
      negforms = nil,
      help = 'Display this help message and exit'
    }

    opts.version = {
      type = 'boolean', val = nil,
      forms = {'-v', '--version'},
      negforms = nil,
      help = 'Display version info and exit'
    }

    opts.save = {
      type = 'boolean', val = nil,
      forms = {'-s', '--save'},
      negforms = nil,
      help = 'Save some settings to configuration file'
    }

    opts.debug = {
      type = 'boolean', val = nil,
      forms = {'-d'},
      negforms = nil,
      help = 'Debug: do not remove temp files'
    }

    opts.gui = {
      type = 'string', val = nil,
      forms = {'--gui'},
      negforms = nil,
      help = nil -- reserved for use by epspdftk
    }

    -- a couple of functions only available during command-line parsing

    local function show_version ()
      print('Epspdf version '..ep_version..'\nCopyright (c) '
          ..ep_copyright..' Siep Kroonenberg')
    end

    local function help (mess) -- requires opts array
      if mess then print(mess..eol) end
      show_version()
      -- below, string.gsub unindents its long-string parameter.
      -- string.format removes the second return value of string.gsub.
      print(string.format('%s', string.gsub([[

      Convert between [e]ps and pdf formats
      Usage: epspdf[.tlu] [options] infile [outfile]
      Default for outfile is file.pdf if infile is file.eps or file.ps
      Default for outfile is file.eps if infile is file.pdf
      ]], '([\r\n]+)      ', '%1')))

      -- need to enforce an ordering, otherwise we could have used pairs(opts)
      -- omitted below: no-op options
      -- one line where possible
      local indent_n = 12
      local intent_sp = string.rep(' ', indent_n)
      local indent_fmt = '%-' .. tostring(indent_n) .. 's'
      for _, o in ipairs({'page', 'gray', 'bbox', 'pdf_target', 'pdf_version',
         'pdftops_prog', 'use_pdftops', 'save', 'info', 'debug',
         'version', 'help'}) do
        local v = opts[o]
        if v~='pdftops_prog' or not auto_psp then
          if v and v.help then
            local synt = join(v.forms, ', ')
            if v.type ~= 'boolean' then synt = synt .. ' ' .. v.placeholder end
            if string.len(synt)<indent_n then
              print(string.format(indent_fmt, synt) .. v.help)
            else
              print(synt)
              print(intent_sp .. v.help)
            end
            if v.negforms then
              local neghelp = 'Reverses the above'
              synt = join(v.negforms, ', ')
              if string.len(synt)<indent_n then
                print(string.format(indent_fmt, synt) .. neghelp)
              else
                print(synt)
                print(intent_sp .. neghelp)
              end
            end
          end
        end -- ~=pdftops_prog or not auto_psp
      end -- for
      if mess then os.exit(1) else os.exit() end
    end -- help

    if #arg < 1 then help('No parameters') end

    -- command-line parsing

    -- -r="tata tata" is parsed by [tex]lua as a single argument
    -- lua/linux retains the quotes,
    -- lua/windows strips them.
    -- texlua strips them, both on unix and on windows.

    local i=1
    while i<=#arg and string.sub(arg[i],1,1)=='-' do
      -- dbg('parse argument '..tostring(i)..': '..arg[i])
      local parsed = false
      local kk, vv = string.match(arg[i],'([^=]+)=(.*)$')
      if kk==nil then
        kk = arg[i] -- also vv==nil
      else
        vv = strip_outer_spaces(vv)
      end
      for p, o in pairs(opts) do
        -- dbg(' try '..p)
        if in_list(kk, o.forms) or in_list(kk, o.negforms) then
          parsed = true
          if o.type == 'boolean' then
            if vv then help(kk..' should not have a parameter.') end
            if in_list(kk, o.forms) then
              o.val = true
            else
              o.val = false
            end
          elseif vv then
            o.val = vv
          else
            i = i + 1
            if i>#arg then
              help('Missing parameter to '..kk)
            end
            o.val = strip_outer_spaces(arg[i])
          end -- testing for o.type or vv
          break -- for
        end -- if in_list
      end -- for
      if not parsed then help('illegal parameter '..kk) end
      i = i + 1
    end -- while

    -- some debug output

    --[[
    if i<=#arg then
      dbg('non-option arguments:')
      for j=i,#arg do dbg(arg[j]) end
      dbg(eol)
    else
      dbg('no non-option arguments')
    end

    for i=1,#arg do dbg(arg[i]) end

    dbg(eol..'Options from command-line:')
    for p, o in pairs(opts) do
      if o.val==nil then
        dbg(p..': undefined')
      else
        dbg(p..': '..tostring(o.val))
      end
    end
      --]]

    -- check and interpret opts.
    -- Copy to either settings or to options table.
    -- at syntax error, abort via help function.

    -- page

    if opts.page.val then
      local pnum = tonumber(opts.page.val)
      if pnum<=0 or math.floor(pnum) ~= pnum then
        help(opts.page.val..' not a positive integer')
      else
        options.page = pnum
      end
    end

    -- grayscaling

    if opts.gray.val then
      options.gray = true
    else
      options.gray = false
    end

    -- boundingbox

    if opts.bbox.val then
      options.bbox = true
    else
      options.bbox = false
    end

    --[[
    -- using hires boundingbox

    if opts.use_hires_bb.val~=nil then
      settings.use_hires_bb = opts.use_hires_bb.val
    end
    --]]

    -- using pdftops

    if opts.use_pdftops.val~=nil then
      settings.use_pdftops = opts.use_pdftops.val
    end

    -- pdf target use

    if opts.pdf_target.val~=nil then
      if in_list(opts.pdf_target.val, pdf_targets) then
        settings.pdf_target = opts.pdf_target.val
      else
        help('Illegal value '..opts.pdf_target.val..' for pdf_target')
      end
    end

    -- pdf version

    if opts.pdf_version.val~=nil then
      if in_list(opts.pdf_version.val, pdf_versions) then
        settings.pdf_version = opts.pdf_version.val
      else
        help('Illegal value '..opts.pdf_version.val..' for pdf_version')
      end
    end

    -- pdftops program; pdftops has already been been initialized to false

    -- pdftops_prog as command-line option
    if os.type=='windows' and not auto_psp and
        opts.pdftops_prog.val then
      settings.pdftops_prog = is_prog(opts.pdftops_prog.val)
    end

    -- pdftops should be on the path. otherwise, make it so if possible.
    if os.type=='windows' and not auto_psp then
      if settings.use_pdftops then
        pdftops = is_prog(settings.pdftops_prog)
        if pdftops then
          -- strip path and modify searchpath, to avoid paths with spaces
          maybe_add_path(string.gsub(pdftops, '[\\/][^\\/]*$', ''), 'append')
          pdftops = string.gsub(settings.pdftops_prog, '^.*[\\/]', '')
        end
      end
    elseif os.type=='windows' then
      if settings.use_pdftops then
        pdftops = 'pdftops.exe'
      end
    else
      if settings.use_pdftops then
        pdftops = find_on_path('pdftops')
      end
    end
    -- dbg('Option handling; pdftops is '..tostring(pdftops))

    -- other options

    if opts.save.val then
      write_settings(rcfile)
    end

    if opts.debug.val then
      options.debug = true
    end

    if opts.help.val then
      help()
    end

    -- opts.info.val: do later; need to get infile first

    if opts.version.val then
      show_version()
      os.exit()
    end

    if opts.gui.val then
      gui(opts.gui.val)
    end

    -- now we need 1 or 2 filenames, unless the user really only
    -- wanted to save options without further action.

    if i>#arg then
      if opts.save.val then os.exit() else help('No filenames') end
    end

    infile = arg[i]
    outfile = false
    if i<#arg then
      outfile = arg[i+1]
    end
    if (#arg>i and opts.info.val) or (#arg>i+1) then
      help('Surplus non-option parameters')
    end

    if not outfile and not opts.info.val then
      -- derive outfile from infile: [e]ps => pdf, pdf => eps
      if intype=='pdf' then
        outfile = string.gsub(infile,'%.[^%.]*$','eps')
      else
        outfile = string.gsub(infile,'%.[^%.]*$','.pdf')
      end
    end

    -- one final quick option
    if opts.info.val then
      info(infile)
    end

    -- add pdf_version and pdf_target to the options array,
    -- from where it will be set to false when realized
    if settings.pdf_target == 'default' then
      options.pdf_target = false
    else
      options.pdf_target = settings.pdf_target
    end
    if settings.pdf_version == 'default' then
      options.pdf_version = false
    else
      options.pdf_version = tonumber(settings.pdf_version)
    end

  end -- decoding command-line

  --[[
  dbg('After command-line processing\n Settings')
  -- print settings- and options array with dbg
  for k, v in pairs(settings) do
    dbg(k..': '..tostring(v))
  end
  dbg(' Options')
  for k, v in pairs(options) do
    dbg(k..': '..tostring(v))
  end
  --]]

  --[[

  Once it becomes clear that real work needs to be done,
  we shall create a temp directory.

    because of gs -dSAFER restrictions, infile must be in (a
    subdirectory of) the directory of the output file, e.g. in the
    temp directory.

    Also because of -dSAFER, we copy infile to the temp directory of
    it is not in the same directory as outfile.

  --]]

  source = io.open(infile)
  if not source then
    error(infile .. ' not readable')
  end
  source:close()
  -- if options.debug then
  --   warn('in: '..infile..'\nout: '..outfile..'\n\ncwd: '..cwd)
  -- end
  infile, in_dir = absolute_path(infile)
  outfile, out_dir = absolute_path(outfile)
  if not out_dir then
    errror('Invalid output directory for '.. outfile)
  end

  -- directory for temporary files

  -- previously, we used a subdirectory of the target directory.
  -- however, since under windows cleanup may fail, we now try to use
  -- a directory under a dedicated temp directory, which has a better chance
  -- of getting cleaned up by the system.

  lfs.chdir(system_tempdir() or out_dir)
  -- no check for failure; we create a subdirectory in
  -- whatever is the current directory
  tempdir = os.tmpdir()
  if not tempdir then
    errror('Cannot create directory for temporary files')
  else
    -- dbg('temp directory '..tempdir)
  end
  lfs.chdir(tempdir)

  intype = identify(infile)

  -- remaining cases: want a real conversion
  if not intype then
    error(infile..' has an unsupported filetype')
  end

  --sanity check on output filetype
  options.type = string.match(outfile, '.*%.([^%.]+)$')
  if not options.type or (options.type~='ps'
      and options.type~='eps' and options.type~='pdf') then
    errror('Output file '..outfile..
        ' should have extension .eps, .ps or .pdf')
  end

  if outfile==infile then
    local insave = infile .. '.luasave'
    move_or_copy(infile, insave)
    infile = insave
  end

  -- had some trouble under msw when removing outfile later so try it now
  if lfs.isfile(outfile) then
    os.remove(outfile)
    -- if removal fails but outfile is overwritable then no real problem
  end

  local fout = io.open(outfile, 'wb')
  if not fout then
    errror('Output file '..outfile..' not writable; aborting')
  else
    fout:close()
  end

  source = PsPdf:from_path(infile)
  dest = source:any_to_any()
  if not lfs.isfile(dest.path) then
    errror('Failed to generate '..dest.path)
  end
  write_log('Copying or moving '..dest.path..' to '..outfile)
  move_or_copy(dest.path, outfile)
  if not options.debug then
    cleantemp()
  end
  if lfs.isfile(outfile) and lfs.attributes(outfile, 'size')>0 then
    os.exit()
  else
    errror('Conversion failed')
  end
end