texk 1

git-svn-id: svn://tug.org/texlive/trunk@1485 c570f23f-e606-0410-a88d-b1316a301751

1 files changed, 816 insertions, 0 deletions

diff --git a/Build/source/texk/web2c/tangle.ch b/Build/source/texk/web2c/tangle.ch
new file mode 100644
index 00000000000..3bb756e7266
--- /dev/null
+++ b/Build/source/texk/web2c/tangle.ch
@@ -0,0 +1,816 @@
+% tangle.ch for C compilation with web2c.
+%
+%  10/9/82 (HT) Original version
+%  11/29   (HT) New version, with conversion to lowercase handled properly
+%               Also, new control sequence:
+%                       @=...text...@>   Put ...text... verbatim on a line
+%                                        by itself in the Pascal output.
+%                                        (argument must fit on one line)
+%               This control sequence facilitates putting #include "gcons.h"
+%               (for example) in files meant for the pc compiler.
+%               Also, changed command line usage, so that the absence of a
+%               change file implies no change file, rather than one with the
+%               same name as the web file, with .ch at the end.
+%  1/15/83 (HT) Changed to work with version 1.2, which incorporates the
+%               above change (though unbundling the output line breaking),
+%               so mainly had to remove stuff.
+%  2/17    (HT) Fixed bug that caused 0-9 in identifiers to be converted to
+%               Q-Y on output.
+%  3/18    (HT) Brought up to work with Version 1.5.  Added -r command line
+%               flag to cause a .rpl file to be written with all the lines
+%               of the .web file that were replaced because of the .ch file
+%               (useful for comparing with previous .rpl files, to see if a
+%               change file will still work with a new version of a .web file)
+%               Also, made it write a newline just before exit.
+%  4/12    (PC) Merged with Pavel's version, including adding a call to exit()
+%               at the end depending upon the value of history.
+%  4/16    (PC) Brought up to date with version 1.5 released April, 1983.
+%  6/28   (HWT) Brought up to date with version 1.7 released June, 1983.
+%               With new change file format, the -r option is now unnecessary.
+%  7/17   (HWT) Brought up to date with version 2.0 released July, 1983.
+% 12/18/83 (ETM) Brought up to date with version 2.5 released November, 1983.
+% 11/07/84 (ETM) Brought up to date with version 2.6.
+% 12/15/85 (ETM) Brought up to date with version 2.8.
+% 03/07/88 (ETM) Converted for use with WEB2C
+% 01/02/89 (PAM) Cosmetic upgrade to version 2.9
+% 11/30/89 (KB)  Version 4.
+% (more recent changes in the ChangeLog)
+
+@x [0] Print only changes.
+\pageno=\contentspagenumber \advance\pageno by 1
+@y
+\pageno=\contentspagenumber \advance\pageno by 1
+\let\maybe=\iffalse
+\def\title{TANGLE changes for C}
+@z
+
+@x [2] Define and call parse_arguments.
+procedure initialize;
+  var @<Local variables for initialization@>@/
+  begin @<Set initial values@>@/
+@y
+@<Define |parse_arguments|@>
+procedure initialize;
+  var @<Local variables for initialization@>@/
+  begin
+    kpse_set_progname (argv[0]);
+    parse_arguments;
+    @<Set initial values@>@/
+@z
+
+@x [8] Constants: increase id lengths, for TeX--XeT and tex2pdf.
+@!buf_size=100; {maximum length of input line}
+@y
+@!buf_size=3000; {maximum length of input line}
+@z
+@x
+@!max_toks=50000; {|1/zz| times the number of bytes in compressed \PASCAL\ code;
+  must be less than 65536}
+@!max_names=4000; {number of identifiers, strings, module names;
+  must be less than 10240}
+@!max_texts=2000; {number of replacement texts, must be less than 10240}
+@y
+@!max_toks=60000; {|1/zz| times the number of bytes in compressed \PASCAL\ code;
+  must be less than 65536}
+@!max_names=10000; {number of identifiers, strings, module names;
+  must be less than 10240}
+@!max_texts=10000; {number of replacement texts, must be less than 10240}
+@z
+
+@x
+@!stack_size=50; {number of simultaneous levels of macro expansion}
+@!max_id_length=12; {long identifiers are chopped to this length, which must
+  not exceed |line_length|}
+@!unambig_length=7; {identifiers must be unique if chopped to this length}
+  {note that 7 is more strict than \PASCAL's 8, but this can be varied}
+@y
+@!stack_size=100; {number of simultaneous levels of macro expansion}
+@!max_id_length=50; {long identifiers are chopped to this length, which must
+  not exceed |line_length|}
+@!def_unambig_length=32; {identifiers must be unique if chopped to this length}
+@z
+
+% [??] The text_char type is used as an array index into xord.  The
+% default type `char' produces signed integers, which are bad array
+% indices in C.
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% 
+@x
+@d text_char == char {the data type of characters in text files}
+@y
+@d text_char == ASCII_code {the data type of characters in text files}
+@z
+
+@x [17] enable maximum character set
+for i:=1 to @'37 do xchr[i]:=' ';
+for i:=@'200 to @'377 do xchr[i]:=' ';
+@y
+for i:=1 to @'37 do xchr[i]:=chr(i);
+for i:=@'200 to @'377 do xchr[i]:=chr(i);
+@z
+
+@x [20] terminal output: use standard i/o
+@d print(#)==write(term_out,#) {`|print|' means write on the terminal}
+@y
+@d term_out==stdout
+@d print(#)==write(term_out,#) {`|print|' means write on the terminal}
+@z
+
+@x
+@<Globals...@>=
+@!term_out:text_file; {the terminal as an output file}
+@y
+@z
+
+@x [21] init terminal
+@ Different systems have different ways of specifying that the output on a
+certain file will appear on the user's terminal. Here is one way to do this
+on the \PASCAL\ system that was used in \.{TANGLE}'s initial development:
+@^system dependencies@>
+
+@<Set init...@>=
+rewrite(term_out,'TTY:'); {send |term_out| output to the terminal}
+@y
+@ Different systems have different ways of specifying that the output on a
+certain file will appear on the user's terminal.
+@^system dependencies@>
+
+@<Set init...@>=
+ {Nothing need be done for C.}
+@z
+
+@x [22] flush terminal buffer
+@d update_terminal == break(term_out) {empty the terminal output buffer}
+@y
+@d update_terminal == fflush(term_out) {empty the terminal output buffer}
+@z
+
+@x [24] open input files
+begin reset(web_file); reset(change_file);
+@y
+begin web_file := kpse_open_file(web_name, kpse_web_format);
+if chg_name then change_file := kpse_open_file(chg_name, kpse_web_format);
+@z
+
+@x [26] Open output files (except for the pool file).
+rewrite(Pascal_file); rewrite(pool);
+@y
+rewrite (Pascal_file, pascal_name);
+@z
+
+@x [28] Fix f^.
+    begin buffer[limit]:=xord[f^]; get(f);
+    incr(limit);
+    if buffer[limit-1]<>" " then final_limit:=limit;
+    if limit=buf_size then
+      begin while not eoln(f) do get(f);
+@y
+    begin buffer[limit]:=xord[getc(f)];
+    incr(limit);
+    if buffer[limit-1]<>" " then final_limit:=limit;
+    if limit=buf_size then
+      begin while not eoln(f) do vgetc(f);
+@z
+
+@x [??] Fix `jump_out'.
+@d fatal_error(#)==begin new_line; print(#); error; mark_fatal; jump_out;
+  end
+
+@<Error handling...@>=
+procedure jump_out;
+begin goto end_of_TANGLE;
+end;
+@y
+@d jump_out==uexit(1)
+@d fatal_error(#)==begin new_line; write(stderr, #); 
+     error; mark_fatal; uexit(1);
+  end
+@z
+
+@x [38] Provide for a larger `byte_mem' and `tok_mem'. Extra capacity:
+@d ww=2 {we multiply the byte capacity by approximately this amount}
+@d zz=3 {we multiply the token capacity by approximately this amount}
+@y
+@d ww=3 {we multiply the byte capacity by approximately this amount}
+@d zz=5 {we multiply the token capacity by approximately this amount}
+@z
+
+@x [38] Provide for larger than 16bit numeric macros.
+@!equiv: array [0..max_names] of sixteen_bits; {info corresponding to names}
+@y
+@!equiv: array [0..max_names] of integer; {info corresponding to names}
+@z
+
+@x [47] Provide for larger than 16bit numeric macros.
+their |equiv| value contains the corresponding numeric value plus $2^{15}$.
+@y
+their |equiv| value contains the corresponding numeric value plus $2^{30}$.
+@z
+
+@x [47] Add parametric2 macros (macros that use [] to delimit arguments).
+\yskip\hang |parametric| identifiers have been defined to be parametric macros;
+like simple identifiers, their |equiv| value points to the replacement text.
+@y
+\yskip\hang |parametric| and |parametric2| identifiers have been defined to
+be parametric macros; like simple identifiers, their |equiv| value points to
+the replacement text.
+@z
+@x
+@d parametric=3 {parametric macros have |parametric| ilk}
+@y
+@d parametric=3 {parametric macros have |parametric| ilk}
+@d parametric2=4 {second type of parametric macros have this |ilk|}
+@z
+
+@x [50] unambig_length is a variabe now
+@!chopped_id:array [0..unambig_length] of ASCII_code; {chopped identifier}
+@y
+@!chopped_id:array [0..max_id_length] of ASCII_code; {chopped identifier}
+@z
+
+@x [53] Add parametric2 macros (macros that use [] to delimit arguments).
+|numeric|, |simple|, or |parametric|.
+@y
+|numeric|, |simple|, |parametric|, or |parametric2|.
+@z
+
+@x [53] unambig_length is a variable.
+@!s:0..unambig_length; {index into |chopped_id|}
+@y
+@!s:0..max_id_length; {index into |chopped_id|}
+@z
+
+@x [58] Case smashing options/strict checking.
+  begin if buffer[i]<>"_" then
+    begin if buffer[i]>="a" then chopped_id[s]:=buffer[i]-@'40
+@y
+  begin if (buffer[i]<>"_") or (allow_underlines and not strict_mode) then
+    begin if (strict_mode or force_uppercase) and (buffer[i]>="a") then
+      chopped_id[s]:=buffer[i]-@'40
+    else if (not strict_mode and force_lowercase)
+           and (buffer[i]>="A") and (buffer[i]<="Z") then
+      chopped_id[s]:=buffer[i]+@'40
+@z
+
+@x [63] Case smashing options/strict checking.
+  if c<>"_" then
+    begin if c>="a" then c:=c-@'40; {merge lowercase with uppercase}
+@y
+  if c<>"_" or (allow_underlines and not strict_mode) then
+    begin if (strict_mode or force_uppercase) and (c>="a") then c:=c-@'40
+    else if (not strict_mode and force_lowercase)
+           and (c>="A") and (c<="Z") then
+      c:=c+@'40;
+@z
+
+@x [64] Delayed pool file opening / larger numerics.
+@<Define and output a new string...@>=
+begin ilk[p]:=numeric; {strings are like numeric macros}
+if l-double_chars=2 then {this string is for a single character}
+  equiv[p]:=buffer[id_first+1]+@'100000
+else  begin equiv[p]:=string_ptr+@'100000;
+  l:=l-double_chars-1;
+@y
+@<Define and output a new string...@>=
+begin ilk[p]:=numeric; {strings are like numeric macros}
+if l-double_chars=2 then {this string is for a single character}
+  equiv[p]:=buffer[id_first+1]+@'10000000000
+else  begin
+  {Avoid creating empty pool files.}
+  if string_ptr = 256 then begin
+    {Change |".web"| to |".pool"| and use the current directory.}
+    pool_name := basename_change_suffix (web_name, '.web', '.pool');
+    rewritebin (pool, pool_name);
+  end;
+  equiv[p]:=string_ptr+@'10000000000;
+  l:=l-double_chars-1;
+@z
+
+@x [85] Add parametric2 macros (macros that use [] to delimit arguments).
+  begin if ilk[cur_name]=parametric then
+@y
+  begin if (ilk[cur_name]=parametric) or (ilk[cur_name]=parametric2) then
+@z
+
+@x [89] Larger numerics.
+numeric: begin cur_val:=equiv[a]-@'100000; a:=number;
+@y
+numeric: begin cur_val:=equiv[a]-@'10000000000; a:=number;
+@z
+
+@x [89] Add parametric2 macros (macros that use [] to delimit arguments).
+parametric: begin @<Put a parameter on the parameter stack,
+@y
+parametric,parametric2: begin @<Put a parameter on the parameter stack,
+@z
+
+@x [90] Add parametric2 macros (macros that use [] to delimit arguments).
+if (stack_ptr=0)or(tok_mem[zo,cur_byte]<>"(") then
+@y
+if (stack_ptr=0)or((ilk[a]=parametric)and(tok_mem[zo,cur_byte]<>"("))
+    or((ilk[a]=parametric2)and(tok_mem[zo,cur_byte]<>"[")) then
+@z
+
+@x [93] Add parametric2 macros (macros that use [] to delimit arguments).
+bal:=1; incr(cur_byte); {skip the opening `\.('}
+@y
+bal:=1; incr(cur_byte); {skip the opening `\.(' or `['}
+@z
+@x
+      "(": incr(bal);
+      ")":  begin decr(bal);
+@y
+      "(": if ilk[a]=parametric then incr(bal);
+      ")": if ilk[a]=parametric then begin decr(bal);
+        if bal=0 then goto done;
+        end;
+      "[": if ilk[a]=parametric2 then incr(bal);
+      "]": if ilk[a]=parametric2 then begin decr(bal);
+@z
+
+@x [105] Accept DIV, div, MOD, and mod
+ (((out_contrib[1]="D")and(out_contrib[2]="I")and(out_contrib[3]="V")) or@|
+ ((out_contrib[1]="M")and(out_contrib[2]="O")and(out_contrib[3]="D")) ))or@|
+@^uppercase@>
+@y
+  (((out_contrib[1]="D")and(out_contrib[2]="I")and(out_contrib[3]="V")) or@|
+  ((out_contrib[1]="d")and(out_contrib[2]="i")and(out_contrib[3]="v")) or@|
+  ((out_contrib[1]="M")and(out_contrib[2]="O")and(out_contrib[3]="D")) or@|
+  ((out_contrib[1]="m")and(out_contrib[2]="o")and(out_contrib[3]="d")) ))or@|
+@z
+
+@x [110] lowercase ids
+@^uppercase@>
+  if ((out_buf[out_ptr-3]="D")and(out_buf[out_ptr-2]="I")and
+    (out_buf[out_ptr-1]="V"))or @/
+     ((out_buf[out_ptr-3]="M")and(out_buf[out_ptr-2]="O")and
+    (out_buf[out_ptr-1]="D")) then@/ goto bad_case
+@y
+  if ((out_buf[out_ptr-3]="D")and(out_buf[out_ptr-2]="I")and
+    (out_buf[out_ptr-1]="V"))or @/
+     ((out_buf[out_ptr-3]="d")and(out_buf[out_ptr-2]="i")and
+    (out_buf[out_ptr-1]="v"))or @/
+     ((out_buf[out_ptr-3]="M")and(out_buf[out_ptr-2]="O")and
+    (out_buf[out_ptr-1]="D"))or @/
+     ((out_buf[out_ptr-3]="m")and(out_buf[out_ptr-2]="o")and
+    (out_buf[out_ptr-1]="d")) then@/ goto bad_case
+@z
+
+@x [114] lowercase operators (`and', `or', etc.)
+and_sign: begin out_contrib[1]:="A"; out_contrib[2]:="N"; out_contrib[3]:="D";
+@^uppercase@>
+  send_out(ident,3);
+  end;
+not_sign: begin out_contrib[1]:="N"; out_contrib[2]:="O"; out_contrib[3]:="T";
+  send_out(ident,3);
+  end;
+set_element_sign: begin out_contrib[1]:="I"; out_contrib[2]:="N";
+  send_out(ident,2);
+  end;
+or_sign: begin out_contrib[1]:="O"; out_contrib[2]:="R"; send_out(ident,2);
+@y
+and_sign: begin out_contrib[1]:="a"; out_contrib[2]:="n"; out_contrib[3]:="d";
+  send_out(ident,3);
+  end;
+not_sign: begin out_contrib[1]:="n"; out_contrib[2]:="o"; out_contrib[3]:="t";
+  send_out(ident,3);
+  end;
+set_element_sign: begin out_contrib[1]:="i"; out_contrib[2]:="n";
+  send_out(ident,2);
+  end;
+or_sign: begin out_contrib[1]:="o"; out_contrib[2]:="r"; send_out(ident,2);
+@z
+
+@x [116] Case smashing options.
+@ Single-character identifiers represent themselves, while longer ones
+appear in |byte_mem|. All must be converted to uppercase,
+with underlines removed. Extremely long identifiers must be chopped.
+
+(Some \PASCAL\ compilers work with lowercase letters instead of
+uppercase. If this module of \.{TANGLE} is changed, it's also necessary
+to change from uppercase to lowercase in the modules that are
+listed in the index under ``uppercase''.)
+@^system dependencies@>
+@^uppercase@>
+
+@d up_to(#)==#-24,#-23,#-22,#-21,#-20,#-19,#-18,#-17,#-16,#-15,#-14,
+  #-13,#-12,#-11,#-10,#-9,#-8,#-7,#-6,#-5,#-4,#-3,#-2,#-1,#
+
+@<Cases related to identifiers@>=
+"A",up_to("Z"): begin out_contrib[1]:=cur_char; send_out(ident,1);
+  end;
+"a",up_to("z"): begin out_contrib[1]:=cur_char-@'40; send_out(ident,1);
+  end;
+identifier: begin k:=0; j:=byte_start[cur_val]; w:=cur_val mod ww;
+  while (k<max_id_length)and(j<byte_start[cur_val+ww]) do
+    begin incr(k); out_contrib[k]:=byte_mem[w,j]; incr(j);
+    if out_contrib[k]>="a" then out_contrib[k]:=out_contrib[k]-@'40
+    else if out_contrib[k]="_" then decr(k);
+    end;
+  send_out(ident,k);
+  end;
+@y
+@ Single-character identifiers represent themselves, while longer ones
+appear in |byte_mem|. All must be converted to lowercase,
+with underlines removed. Extremely long identifiers must be chopped.
+@^system dependencies@>
+
+@d up_to(#)==#-24,#-23,#-22,#-21,#-20,#-19,#-18,#-17,#-16,#-15,#-14,
+  #-13,#-12,#-11,#-10,#-9,#-8,#-7,#-6,#-5,#-4,#-3,#-2,#-1,#
+
+@<Cases related to identifiers@>=
+"A",up_to("Z"): begin if force_lowercase then out_contrib[1]:=cur_char+@'40
+    else out_contrib[1]:=cur_char;
+    send_out(ident,1);
+  end;
+"a",up_to("z"): begin if force_uppercase then out_contrib[1]:=cur_char-@'40
+    else out_contrib[1]:=cur_char;
+    send_out(ident,1);
+  end;
+identifier: begin k:=0; j:=byte_start[cur_val]; w:=cur_val mod ww;
+  while (k<max_id_length)and(j<byte_start[cur_val+ww]) do
+    begin incr(k); out_contrib[k]:=byte_mem[w,j]; incr(j);
+    if force_uppercase and (out_contrib[k]>="a") then
+      out_contrib[k]:=out_contrib[k]-@'40
+    else if force_lowercase and (out_contrib[k]<="Z") then
+      out_contrib[k]:=out_contrib[k]+@'40
+    else if not allow_underlines and (out_contrib[k]="_") then decr(k);
+    end;
+  send_out(ident,k);
+  end;
+@z
+
+@x [119] Stretch limits of constants to match what we set for expressions.
+  if n>=@'2000000000 then err_print('! Constant too big')
+@y
+  if n>=@'10000000000 then err_print('! Constant too big')
+@z
+@x
+  if n>=@"8000000 then err_print('! Constant too big')
+@y
+  if n>=@"40000000 then err_print('! Constant too big')
+@z
+
+@x [157] Fix casting bug
+@d add_in(#)==begin accumulator:=accumulator+next_sign*(#); next_sign:=+1;
+  end
+@y
+@d add_in(#)==begin accumulator:=accumulator+next_sign*intcast(#); next_sign:=+1;
+  end
+@z
+
+@x [157] Larger numerics.
+if abs(accumulator)>=@'100000 then
+@y
+if abs(accumulator)>=@'10000000000 then
+@z
+
+@x [157] Larger numerics.
+equiv[p]:=accumulator+@'100000; {name |p| now is defined to equal |accumulator|}
+@y
+equiv[p]:=accumulator+@'10000000000; {name |p| now is defined to equal |accumulator|}
+@z
+
+@x [158] Larger numerics.
+    add_in(equiv[q]-@'100000);
+@y
+    add_in(equiv[q]-@'10000000000);
+@z
+
+@x [165] Add parametric2 macros (macros that use [] to delimit arguments).
+  "(": incr(bal);
+  ")": if bal=0 then err_print('! Extra )')
+@.Extra )@>
+    else decr(bal);
+  "'": @<Copy a string from the buffer to |tok_mem|@>;
+  "#": if t=parametric then a:=param;
+@y
+  "(": if t=parametric then incr(bal);
+  ")": if t=parametric then if bal=0 then err_print('! Extra )')
+@.Extra )@>
+    else decr(bal);
+  "[": if t=parametric2 then incr(bal);
+  "]": if t=parametric2 then if bal=0 then err_print('! Extra ]')
+@.Extra ]@>
+    else decr(bal);
+  "'": @<Copy a string from the buffer to |tok_mem|@>;
+  "#": if (t=parametric)or(t=parametric2) then a:=param;
+@z
+
+@x [166] Add parametric2 macros (macros that use [] to delimit arguments).
+  begin if bal=1 then err_print('! Missing )')
+  else err_print('! Missing ',bal:1,' )''s');
+@.Missing n )@>
+  while bal>0 do
+    begin app_repl(")"); decr(bal);
+    end;
+  end
+@y
+  if t=parametric then begin
+    if bal=1 then err_print('! Missing )')
+    else err_print('! Missing ',bal:1,' )''s');
+@.Missing n )@>
+    while bal>0 do
+      begin app_repl(")"); decr(bal);
+      end;
+    end
+  else begin
+    if bal=1 then err_print('! Missing ]')
+    else err_print('! Missing ',bal:1,' ]''s');
+@.Missing n ]@>
+    while bal>0 do
+      begin app_repl("]"); decr(bal);
+      end;
+    end
+@z
+
+@x [173] Add parametric2 macros (macros that use [] to delimit arguments).
+  else @<If the next text is `|(#)==|', call |define_macro|
+    and |goto continue|@>;
+@y
+  else @<If the next text is `|(#)==|' or |[#]==|, call |define_macro|
+    and |goto continue|@>;
+@z
+
+@x [174] Add parametric2 macros (macros that use [] to delimit arguments).
+@ @<If the next text is `|(#)==|'...@>=
+if next_control="(" then
+  begin next_control:=get_next;
+  if next_control="#" then
+    begin next_control:=get_next;
+    if next_control=")" then
+      begin next_control:=get_next;
+      if next_control="=" then
+        begin err_print('! Use == for macros');
+@.Use == for macros@>
+        next_control:=equivalence_sign;
+        end;
+      if next_control=equivalence_sign then
+        begin define_macro(parametric); goto continue;
+        end;
+      end;
+    end;
+  end;
+@y
+@ @<If the next text is `|(#)==|'...@>=
+if next_control="(" then
+  begin next_control:=get_next;
+  if next_control="#" then
+    begin next_control:=get_next;
+    if next_control=")" then
+      begin next_control:=get_next;
+      if next_control="=" then
+        begin err_print('! Use == for macros');
+@.Use == for macros@>
+        next_control:=equivalence_sign;
+        end;
+      if next_control=equivalence_sign then
+        begin define_macro(parametric); goto continue;
+        end;
+      end;
+    end;
+  end
+else if next_control="[" then
+  begin next_control:=get_next;
+  if next_control="#" then
+    begin next_control:=get_next;
+    if next_control="]" then
+      begin next_control:=get_next;
+      if next_control="=" then
+        begin err_print('! Use == for macros');
+@.Use == for macros@>
+        next_control:=equivalence_sign;
+        end;
+      if next_control=equivalence_sign then
+        begin define_macro(parametric2); goto continue;
+        end;
+      end;
+    end;
+  end
+@z
+
+@x [179] make term_in = input
+any error stop will set |debug_cycle| to zero.
+@y
+any error stop will set |debug_cycle| to zero.
+
+@d term_in==stdin
+@z
+
+@x
+@!term_in:text_file; {the user's terminal as an input file}
+@y
+@z
+
+@x [180] remove term_in reset
+reset(term_in,'TTY:','/I'); {open |term_in| as the terminal, don't do a |get|}
+@y
+@z
+
+@x [182] write newline just before exit; use value of |history|
+print_ln(banner); {print a ``banner line''}
+@y
+print (banner); {print a ``banner line''}
+print_ln (version_string);
+@z
+
+@x
+@<Print the job |history|@>;
+@y
+@<Print the job |history|@>;
+new_line;
+if (history <> spotless) and (history <> harmless_message)
+then uexit (1)
+else uexit (0);
+@z
+
+@x [188] System-dependent changes.
+This module should be replaced, if necessary, by changes to the program
+that are necessary to make \.{TANGLE} work at a particular installation.
+It is usually best to design your change file so that all changes to
+previous modules preserve the module numbering; then everybody's version
+will be consistent with the printed program. More extensive changes,
+which introduce new modules, can be inserted here; then only the index
+itself will get a new module number.
+@^system dependencies@>
+@y
+Parse a Unix-style command line.
+
+@d argument_is (#) == (strcmp (long_options[option_index].name, #) = 0)
+
+@<Define |parse_arguments|@> =
+procedure parse_arguments;
+const n_options = 10; {Pascal won't count array lengths for us.}
+var @!long_options: array[0..n_options] of getopt_struct;
+    @!getopt_return_val: integer;
+    @!option_index: c_int_type;
+    @!current_option: 0..n_options;
+    @!len: integer;
+begin
+  @<Define the option table@>;
+  unambig_length := def_unambig_length;
+  repeat
+    getopt_return_val := getopt_long_only (argc, argv, '', long_options,
+                                           address_of (option_index));
+    if getopt_return_val = -1 then begin
+      {End of arguments; we exit the loop below.} ;
+    
+    end else if getopt_return_val = "?" then begin
+      usage ('tangle');
+
+    end else if argument_is ('help') then begin
+      usage_help (TANGLE_HELP, nil);
+
+    end else if argument_is ('version') then begin
+      print_version_and_exit (banner, nil, 'D.E. Knuth');
+
+    end else if argument_is ('mixedcase') then begin
+      force_uppercase := false;
+      force_lowercase := false;
+
+    end else if argument_is ('uppercase') then begin
+      force_uppercase := true;
+      force_lowercase := false;
+
+    end else if argument_is ('lowercase') then begin
+      force_uppercase := false;
+      force_lowercase := true;
+
+    end else if argument_is ('underlines') then begin
+      allow_underlines := true;
+
+    end else if argument_is ('strict') then begin
+      strict_mode := true;
+
+    end else if argument_is ('loose') then begin
+      strict_mode := false;
+
+    end else if argument_is ('length') then begin
+      len := atoi(optarg);
+      if (len<=0) or (len>max_id_length) then len := max_id_length;
+      unambig_length := len;
+
+    end; {Else it was a flag; |getopt| has already done the assignment.}
+  until getopt_return_val = -1;
+
+  {Now |optind| is the index of first non-option on the command line.}
+  if (optind + 1 <> argc) and (optind + 2 <> argc) then begin
+    write_ln (stderr, 'tangle: Need one or two file arguments.');
+    usage ('tangle');
+  end;
+  
+  {Supply |".web"| and |".ch"| extensions if necessary.}
+  web_name := extend_filename (cmdline (optind), 'web');
+  if optind + 2 = argc then begin
+    chg_name := extend_filename (cmdline (optind + 1), 'ch');
+  end;
+  
+  {Change |".web"| to |".p"| and use the current directory.}
+  pascal_name := basename_change_suffix (web_name, '.web', '.p');
+end;
+
+@ Here are the options we allow.  The first is one of the standard GNU options.
+@.-help@>
+
+@<Define the option...@> =
+current_option := 0;
+long_options[current_option].name := 'help';
+long_options[current_option].has_arg := 0;
+long_options[current_option].flag := 0;
+long_options[current_option].val := 0;
+incr (current_option);
+
+@ Another of the standard options.
+@.-version@>
+
+@<Define the option...@> =
+long_options[current_option].name := 'version';
+long_options[current_option].has_arg := 0;
+long_options[current_option].flag := 0;
+long_options[current_option].val := 0;
+incr (current_option);
+
+@ Use all mixed case.
+@.-mixedcase@>
+
+@<Define the option...@> =
+long_options[current_option].name := 'mixedcase';
+long_options[current_option].has_arg := 0;
+long_options[current_option].flag := 0;
+long_options[current_option].val := 0;
+incr (current_option);
+
+@ Use all uppercase.
+@.-uppercase@>
+
+@<Define the option...@> =
+long_options[current_option].name := 'uppercase';
+long_options[current_option].has_arg := 0;
+long_options[current_option].flag := 0;
+long_options[current_option].val := 0;
+incr (current_option);
+
+@ Use all lowercase.
+@.-lowercase@>
+
+@<Define the option...@> =
+long_options[current_option].name := 'lowercase';
+long_options[current_option].has_arg := 0;
+long_options[current_option].flag := 0;
+long_options[current_option].val := 0;
+incr (current_option);
+
+@ Allow underlines.
+@.-underlines@>
+
+@<Define the option...@> =
+long_options[current_option].name := 'underlines';
+long_options[current_option].has_arg := 0;
+long_options[current_option].flag := 0;
+long_options[current_option].val := 0;
+incr (current_option);
+
+@ Strict comparisions.
+@.-strict@>
+
+@<Define the option...@> =
+long_options[current_option].name := 'strict';
+long_options[current_option].has_arg := 0;
+long_options[current_option].flag := 0;
+long_options[current_option].val := 0;
+incr (current_option);
+
+@ Loose comparisions.
+@.-loose@>
+
+@<Define the option...@> =
+long_options[current_option].name := 'loose';
+long_options[current_option].has_arg := 0;
+long_options[current_option].flag := 0;
+long_options[current_option].val := 0;
+incr (current_option);
+
+@ Loose comparisions.
+@.-length@>
+
+@<Define the option...@> =
+long_options[current_option].name := 'length';
+long_options[current_option].has_arg := 1;
+long_options[current_option].flag := 0;
+long_options[current_option].val := 0;
+incr (current_option);
+
+@ An element with all zeros always ends the list.
+
+@<Define the option...@> =
+long_options[current_option].name := 0;
+long_options[current_option].has_arg := 0;
+long_options[current_option].flag := 0;
+long_options[current_option].val := 0;
+
+@ Global filenames.
+
+@<Globals...@>=
+@!web_name,@!chg_name,@!pascal_name,@!pool_name:c_string;
+@!force_uppercase,@!force_lowercase,@!allow_underlines,@!strict_mode:boolean;
+@!unambig_length:0..max_id_length;
+@z