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diff --git a/Master/tlpkg/tlperl.straw/lib/pods/perlebcdic.pod b/Master/tlpkg/tlperl.straw/lib/pods/perlebcdic.pod new file mode 100755 index 00000000000..39ed61279cb --- /dev/null +++ b/Master/tlpkg/tlperl.straw/lib/pods/perlebcdic.pod @@ -0,0 +1,1427 @@ +=head1 NAME + +perlebcdic - Considerations for running Perl on EBCDIC platforms + +=head1 DESCRIPTION + +An exploration of some of the issues facing Perl programmers +on EBCDIC based computers. We do not cover localization, +internationalization, or multi byte character set issues other +than some discussion of UTF-8 and UTF-EBCDIC. + +Portions that are still incomplete are marked with XXX. + +=head1 COMMON CHARACTER CODE SETS + +=head2 ASCII + +The American Standard Code for Information Interchange (ASCII or US-ASCII) is a +set of +integers running from 0 to 127 (decimal) that imply character +interpretation by the display and other systems of computers. +The range 0..127 can be covered by setting the bits in a 7-bit binary +digit, hence the set is sometimes referred to as a "7-bit ASCII". +ASCII was described by the American National Standards Institute +document ANSI X3.4-1986. It was also described by ISO 646:1991 +(with localization for currency symbols). The full ASCII set is +given in the table below as the first 128 elements. Languages that +can be written adequately with the characters in ASCII include +English, Hawaiian, Indonesian, Swahili and some Native American +languages. + +There are many character sets that extend the range of integers +from 0..2**7-1 up to 2**8-1, or 8 bit bytes (octets if you prefer). +One common one is the ISO 8859-1 character set. + +=head2 ISO 8859 + +The ISO 8859-$n are a collection of character code sets from the +International Organization for Standardization (ISO) each of which +adds characters to the ASCII set that are typically found in European +languages many of which are based on the Roman, or Latin, alphabet. + +=head2 Latin 1 (ISO 8859-1) + +A particular 8-bit extension to ASCII that includes grave and acute +accented Latin characters. Languages that can employ ISO 8859-1 +include all the languages covered by ASCII as well as Afrikaans, +Albanian, Basque, Catalan, Danish, Faroese, Finnish, Norwegian, +Portuguese, Spanish, and Swedish. Dutch is covered albeit without +the ij ligature. French is covered too but without the oe ligature. +German can use ISO 8859-1 but must do so without German-style +quotation marks. This set is based on Western European extensions +to ASCII and is commonly encountered in world wide web work. +In IBM character code set identification terminology ISO 8859-1 is +also known as CCSID 819 (or sometimes 0819 or even 00819). + +=head2 EBCDIC + +The Extended Binary Coded Decimal Interchange Code refers to a +large collection of slightly different single and multi byte +coded character sets that are different from ASCII or ISO 8859-1 +and typically run on host computers. The EBCDIC encodings derive +from 8 bit byte extensions of Hollerith punched card encodings. +The layout on the cards was such that high bits were set for the +upper and lower case alphabet characters [a-z] and [A-Z], but there +were gaps within each Latin alphabet range. + +Some IBM EBCDIC character sets may be known by character code set +identification numbers (CCSID numbers) or code page numbers. Leading +zero digits in CCSID numbers within this document are insignificant. +E.g. CCSID 0037 may be referred to as 37 in places. + +Perl can be compiled on platforms that run any of three commonly used EBCDIC +character sets, listed below. + +=head2 The 13 variant characters + +Among IBM EBCDIC character code sets there are 13 characters that +are often mapped to different integer values. Those characters +are known as the 13 "variant" characters and are: + + \ [ ] { } ^ ~ ! # | $ @ ` + +When Perl is compiled for a platform, it looks at some of these characters to +guess which EBCDIC character set the platform uses, and adapts itself +accordingly to that platform. If the platform uses a character set that is not +one of the three Perl knows about, Perl will either fail to compile, or +mistakenly and silently choose one of the three. +They are: + +=head2 0037 + +Character code set ID 0037 is a mapping of the ASCII plus Latin-1 +characters (i.e. ISO 8859-1) to an EBCDIC set. 0037 is used +in North American English locales on the OS/400 operating system +that runs on AS/400 computers. CCSID 37 differs from ISO 8859-1 +in 237 places, in other words they agree on only 19 code point values. + +=head2 1047 + +Character code set ID 1047 is also a mapping of the ASCII plus +Latin-1 characters (i.e. ISO 8859-1) to an EBCDIC set. 1047 is +used under Unix System Services for OS/390 or z/OS, and OpenEdition +for VM/ESA. CCSID 1047 differs from CCSID 0037 in eight places. + +=head2 POSIX-BC + +The EBCDIC code page in use on Siemens' BS2000 system is distinct from +1047 and 0037. It is identified below as the POSIX-BC set. + +=head2 Unicode code points versus EBCDIC code points + +In Unicode terminology a I<code point> is the number assigned to a +character: for example, in EBCDIC the character "A" is usually assigned +the number 193. In Unicode the character "A" is assigned the number 65. +This causes a problem with the semantics of the pack/unpack "U", which +are supposed to pack Unicode code points to characters and back to numbers. +The problem is: which code points to use for code points less than 256? +(for 256 and over there's no problem: Unicode code points are used) +In EBCDIC, for the low 256 the EBCDIC code points are used. This +means that the equivalences + + pack("U", ord($character)) eq $character + unpack("U", $character) == ord $character + +will hold. (If Unicode code points were applied consistently over +all the possible code points, pack("U",ord("A")) would in EBCDIC +equal I<A with acute> or chr(101), and unpack("U", "A") would equal +65, or I<non-breaking space>, not 193, or ord "A".) + +=head2 Remaining Perl Unicode problems in EBCDIC + +=over 4 + +=item * + +Many of the remaining problems seem to be related to case-insensitive matching + +=item * + +The extensions Unicode::Collate and Unicode::Normalized are not +supported under EBCDIC, likewise for the encoding pragma. + +=back + +=head2 Unicode and UTF + +UTF stands for C<Unicode Transformation Format>. +UTF-8 is an encoding of Unicode into a sequence of 8-bit byte chunks, based on +ASCII and Latin-1. +The length of a sequence required to represent a Unicode code point +depends on the ordinal number of that code point, +with larger numbers requiring more bytes. +UTF-EBCDIC is like UTF-8, but based on EBCDIC. + +You may see the term C<invariant> character or code point. +This simply means that the character has the same numeric +value when encoded as when not. +(Note that this is a very different concept from L</The 13 variant characters> +mentioned above.) +For example, the ordinal value of 'A' is 193 in most EBCDIC code pages, +and also is 193 when encoded in UTF-EBCDIC. +All other code points occupy at least two bytes when encoded. +In UTF-8, the code points corresponding to the lowest 128 +ordinal numbers (0 - 127: the ASCII characters) are invariant. +In UTF-EBCDIC, there are 160 invariant characters. +(If you care, the EBCDIC invariants are those characters +which have ASCII equivalents, plus those that correspond to +the C1 controls (80..9f on ASCII platforms).) + +A string encoded in UTF-EBCDIC may be longer (but never shorter) than +one encoded in UTF-8. + +=head2 Using Encode + +Starting from Perl 5.8 you can use the standard new module Encode +to translate from EBCDIC to Latin-1 code points. +Encode knows about more EBCDIC character sets than Perl can currently +be compiled to run on. + + use Encode 'from_to'; + + my %ebcdic = ( 176 => 'cp37', 95 => 'cp1047', 106 => 'posix-bc' ); + + # $a is in EBCDIC code points + from_to($a, $ebcdic{ord '^'}, 'latin1'); + # $a is ISO 8859-1 code points + +and from Latin-1 code points to EBCDIC code points + + use Encode 'from_to'; + + my %ebcdic = ( 176 => 'cp37', 95 => 'cp1047', 106 => 'posix-bc' ); + + # $a is ISO 8859-1 code points + from_to($a, 'latin1', $ebcdic{ord '^'}); + # $a is in EBCDIC code points + +For doing I/O it is suggested that you use the autotranslating features +of PerlIO, see L<perluniintro>. + +Since version 5.8 Perl uses the new PerlIO I/O library. This enables +you to use different encodings per IO channel. For example you may use + + use Encode; + open($f, ">:encoding(ascii)", "test.ascii"); + print $f "Hello World!\n"; + open($f, ">:encoding(cp37)", "test.ebcdic"); + print $f "Hello World!\n"; + open($f, ">:encoding(latin1)", "test.latin1"); + print $f "Hello World!\n"; + open($f, ">:encoding(utf8)", "test.utf8"); + print $f "Hello World!\n"; + +to get four files containing "Hello World!\n" in ASCII, CP 37 EBCDIC, +ISO 8859-1 (Latin-1) (in this example identical to ASCII since only ASCII +characters were printed), and +UTF-EBCDIC (in this example identical to normal EBCDIC since only characters +that don't differ between EBCDIC and UTF-EBCDIC were printed). See the +documentation of Encode::PerlIO for details. + +As the PerlIO layer uses raw IO (bytes) internally, all this totally +ignores things like the type of your filesystem (ASCII or EBCDIC). + +=head1 SINGLE OCTET TABLES + +The following tables list the ASCII and Latin 1 ordered sets including +the subsets: C0 controls (0..31), ASCII graphics (32..7e), delete (7f), +C1 controls (80..9f), and Latin-1 (a.k.a. ISO 8859-1) (a0..ff). In the +table non-printing control character names as well as the Latin 1 +extensions to ASCII have been labelled with character names roughly +corresponding to I<The Unicode Standard, Version 3.0> albeit with +substitutions such as s/LATIN// and s/VULGAR// in all cases, +s/CAPITAL LETTER// in some cases, and s/SMALL LETTER ([A-Z])/\l$1/ +in some other cases (the C<charnames> pragma names unfortunately do +not list explicit names for the C0 or C1 control characters). The +"names" of the C1 control set (128..159 in ISO 8859-1) listed here are +somewhat arbitrary. The differences between the 0037 and 1047 sets are +flagged with ***. The differences between the 1047 and POSIX-BC sets +are flagged with ###. All ord() numbers listed are decimal. If you +would rather see this table listing octal values then run the table +(that is, the pod version of this document since this recipe may not +work with a pod2_other_format translation) through: + +=over 4 + +=item recipe 0 + +=back + + perl -ne 'if(/(.{33})(\d+)\s+(\d+)\s+(\d+)\s+(\d+)/)' \ + -e '{printf("%s%-9o%-9o%-9o%o\n",$1,$2,$3,$4,$5)}' perlebcdic.pod + +If you want to retain the UTF-x code points then in script form you +might want to write: + +=over 4 + +=item recipe 1 + +=back + + open(FH,"<perlebcdic.pod") or die "Could not open perlebcdic.pod: $!"; + while (<FH>) { + if (/(.{33})(\d+)\s+(\d+)\s+(\d+)\s+(\d+)\s+(\d+)\.?(\d*)\s+(\d+)\.?(\d*)/) { + if ($7 ne '' && $9 ne '') { + printf("%s%-9o%-9o%-9o%-9o%-3o.%-5o%-3o.%o\n",$1,$2,$3,$4,$5,$6,$7,$8,$9); + } + elsif ($7 ne '') { + printf("%s%-9o%-9o%-9o%-9o%-3o.%-5o%o\n",$1,$2,$3,$4,$5,$6,$7,$8); + } + else { + printf("%s%-9o%-9o%-9o%-9o%-9o%o\n",$1,$2,$3,$4,$5,$6,$8); + } + } + } + +If you would rather see this table listing hexadecimal values then +run the table through: + +=over 4 + +=item recipe 2 + +=back + + perl -ne 'if(/(.{33})(\d+)\s+(\d+)\s+(\d+)\s+(\d+)/)' \ + -e '{printf("%s%-9X%-9X%-9X%X\n",$1,$2,$3,$4,$5)}' perlebcdic.pod + +Or, in order to retain the UTF-x code points in hexadecimal: + +=over 4 + +=item recipe 3 + +=back + + open(FH,"<perlebcdic.pod") or die "Could not open perlebcdic.pod: $!"; + while (<FH>) { + if (/(.{33})(\d+)\s+(\d+)\s+(\d+)\s+(\d+)\s+(\d+)\.?(\d*)\s+(\d+)\.?(\d*)/) { + if ($7 ne '' && $9 ne '') { + printf("%s%-9X%-9X%-9X%-9X%-2X.%-6X%-2X.%X\n",$1,$2,$3,$4,$5,$6,$7,$8,$9); + } + elsif ($7 ne '') { + printf("%s%-9X%-9X%-9X%-9X%-2X.%-6X%X\n",$1,$2,$3,$4,$5,$6,$7,$8); + } + else { + printf("%s%-9X%-9X%-9X%-9X%-9X%X\n",$1,$2,$3,$4,$5,$6,$8); + } + } + } + + + incomp- incomp- + 8859-1 lete lete + chr 0819 0037 1047 POSIX-BC UTF-8 UTF-EBCDIC + ------------------------------------------------------------------------------------ + <NULL> 0 0 0 0 0 0 + <START OF HEADING> 1 1 1 1 1 1 + <START OF TEXT> 2 2 2 2 2 2 + <END OF TEXT> 3 3 3 3 3 3 + <END OF TRANSMISSION> 4 55 55 55 4 55 + <ENQUIRY> 5 45 45 45 5 45 + <ACKNOWLEDGE> 6 46 46 46 6 46 + <BELL> 7 47 47 47 7 47 + <BACKSPACE> 8 22 22 22 8 22 + <HORIZONTAL TABULATION> 9 5 5 5 9 5 + <LINE FEED> 10 37 21 21 10 21 *** + <VERTICAL TABULATION> 11 11 11 11 11 11 + <FORM FEED> 12 12 12 12 12 12 + <CARRIAGE RETURN> 13 13 13 13 13 13 + <SHIFT OUT> 14 14 14 14 14 14 + <SHIFT IN> 15 15 15 15 15 15 + <DATA LINK ESCAPE> 16 16 16 16 16 16 + <DEVICE CONTROL ONE> 17 17 17 17 17 17 + <DEVICE CONTROL TWO> 18 18 18 18 18 18 + <DEVICE CONTROL THREE> 19 19 19 19 19 19 + <DEVICE CONTROL FOUR> 20 60 60 60 20 60 + <NEGATIVE ACKNOWLEDGE> 21 61 61 61 21 61 + <SYNCHRONOUS IDLE> 22 50 50 50 22 50 + <END OF TRANSMISSION BLOCK> 23 38 38 38 23 38 + <CANCEL> 24 24 24 24 24 24 + <END OF MEDIUM> 25 25 25 25 25 25 + <SUBSTITUTE> 26 63 63 63 26 63 + <ESCAPE> 27 39 39 39 27 39 + <FILE SEPARATOR> 28 28 28 28 28 28 + <GROUP SEPARATOR> 29 29 29 29 29 29 + <RECORD SEPARATOR> 30 30 30 30 30 30 + <UNIT SEPARATOR> 31 31 31 31 31 31 + <SPACE> 32 64 64 64 32 64 + ! 33 90 90 90 33 90 + " 34 127 127 127 34 127 + # 35 123 123 123 35 123 + $ 36 91 91 91 36 91 + % 37 108 108 108 37 108 + & 38 80 80 80 38 80 + ' 39 125 125 125 39 125 + ( 40 77 77 77 40 77 + ) 41 93 93 93 41 93 + * 42 92 92 92 42 92 + + 43 78 78 78 43 78 + , 44 107 107 107 44 107 + - 45 96 96 96 45 96 + . 46 75 75 75 46 75 + / 47 97 97 97 47 97 + 0 48 240 240 240 48 240 + 1 49 241 241 241 49 241 + 2 50 242 242 242 50 242 + 3 51 243 243 243 51 243 + 4 52 244 244 244 52 244 + 5 53 245 245 245 53 245 + 6 54 246 246 246 54 246 + 7 55 247 247 247 55 247 + 8 56 248 248 248 56 248 + 9 57 249 249 249 57 249 + : 58 122 122 122 58 122 + ; 59 94 94 94 59 94 + < 60 76 76 76 60 76 + = 61 126 126 126 61 126 + > 62 110 110 110 62 110 + ? 63 111 111 111 63 111 + @ 64 124 124 124 64 124 + A 65 193 193 193 65 193 + B 66 194 194 194 66 194 + C 67 195 195 195 67 195 + D 68 196 196 196 68 196 + E 69 197 197 197 69 197 + F 70 198 198 198 70 198 + G 71 199 199 199 71 199 + H 72 200 200 200 72 200 + I 73 201 201 201 73 201 + J 74 209 209 209 74 209 + K 75 210 210 210 75 210 + L 76 211 211 211 76 211 + M 77 212 212 212 77 212 + N 78 213 213 213 78 213 + O 79 214 214 214 79 214 + P 80 215 215 215 80 215 + Q 81 216 216 216 81 216 + R 82 217 217 217 82 217 + S 83 226 226 226 83 226 + T 84 227 227 227 84 227 + U 85 228 228 228 85 228 + V 86 229 229 229 86 229 + W 87 230 230 230 87 230 + X 88 231 231 231 88 231 + Y 89 232 232 232 89 232 + Z 90 233 233 233 90 233 + [ 91 186 173 187 91 173 *** ### + \ 92 224 224 188 92 224 ### + ] 93 187 189 189 93 189 *** + ^ 94 176 95 106 94 95 *** ### + _ 95 109 109 109 95 109 + ` 96 121 121 74 96 121 ### + a 97 129 129 129 97 129 + b 98 130 130 130 98 130 + c 99 131 131 131 99 131 + d 100 132 132 132 100 132 + e 101 133 133 133 101 133 + f 102 134 134 134 102 134 + g 103 135 135 135 103 135 + h 104 136 136 136 104 136 + i 105 137 137 137 105 137 + j 106 145 145 145 106 145 + k 107 146 146 146 107 146 + l 108 147 147 147 108 147 + m 109 148 148 148 109 148 + n 110 149 149 149 110 149 + o 111 150 150 150 111 150 + p 112 151 151 151 112 151 + q 113 152 152 152 113 152 + r 114 153 153 153 114 153 + s 115 162 162 162 115 162 + t 116 163 163 163 116 163 + u 117 164 164 164 117 164 + v 118 165 165 165 118 165 + w 119 166 166 166 119 166 + x 120 167 167 167 120 167 + y 121 168 168 168 121 168 + z 122 169 169 169 122 169 + { 123 192 192 251 123 192 ### + | 124 79 79 79 124 79 + } 125 208 208 253 125 208 ### + ~ 126 161 161 255 126 161 ### + <DELETE> 127 7 7 7 127 7 + <C1 0> 128 32 32 32 194.128 32 + <C1 1> 129 33 33 33 194.129 33 + <C1 2> 130 34 34 34 194.130 34 + <C1 3> 131 35 35 35 194.131 35 + <C1 4> 132 36 36 36 194.132 36 + <C1 5> 133 21 37 37 194.133 37 *** + <C1 6> 134 6 6 6 194.134 6 + <C1 7> 135 23 23 23 194.135 23 + <C1 8> 136 40 40 40 194.136 40 + <C1 9> 137 41 41 41 194.137 41 + <C1 10> 138 42 42 42 194.138 42 + <C1 11> 139 43 43 43 194.139 43 + <C1 12> 140 44 44 44 194.140 44 + <C1 13> 141 9 9 9 194.141 9 + <C1 14> 142 10 10 10 194.142 10 + <C1 15> 143 27 27 27 194.143 27 + <C1 16> 144 48 48 48 194.144 48 + <C1 17> 145 49 49 49 194.145 49 + <C1 18> 146 26 26 26 194.146 26 + <C1 19> 147 51 51 51 194.147 51 + <C1 20> 148 52 52 52 194.148 52 + <C1 21> 149 53 53 53 194.149 53 + <C1 22> 150 54 54 54 194.150 54 + <C1 23> 151 8 8 8 194.151 8 + <C1 24> 152 56 56 56 194.152 56 + <C1 25> 153 57 57 57 194.153 57 + <C1 26> 154 58 58 58 194.154 58 + <C1 27> 155 59 59 59 194.155 59 + <C1 28> 156 4 4 4 194.156 4 + <C1 29> 157 20 20 20 194.157 20 + <C1 30> 158 62 62 62 194.158 62 + <C1 31> 159 255 255 95 194.159 255 ### + <NON-BREAKING SPACE> 160 65 65 65 194.160 128.65 + <INVERTED EXCLAMATION MARK> 161 170 170 170 194.161 128.66 + <CENT SIGN> 162 74 74 176 194.162 128.67 ### + <POUND SIGN> 163 177 177 177 194.163 128.68 + <CURRENCY SIGN> 164 159 159 159 194.164 128.69 + <YEN SIGN> 165 178 178 178 194.165 128.70 + <BROKEN BAR> 166 106 106 208 194.166 128.71 ### + <SECTION SIGN> 167 181 181 181 194.167 128.72 + <DIAERESIS> 168 189 187 121 194.168 128.73 *** ### + <COPYRIGHT SIGN> 169 180 180 180 194.169 128.74 + <FEMININE ORDINAL INDICATOR> 170 154 154 154 194.170 128.81 + <LEFT POINTING GUILLEMET> 171 138 138 138 194.171 128.82 + <NOT SIGN> 172 95 176 186 194.172 128.83 *** ### + <SOFT HYPHEN> 173 202 202 202 194.173 128.84 + <REGISTERED TRADE MARK SIGN> 174 175 175 175 194.174 128.85 + <MACRON> 175 188 188 161 194.175 128.86 ### + <DEGREE SIGN> 176 144 144 144 194.176 128.87 + <PLUS-OR-MINUS SIGN> 177 143 143 143 194.177 128.88 + <SUPERSCRIPT TWO> 178 234 234 234 194.178 128.89 + <SUPERSCRIPT THREE> 179 250 250 250 194.179 128.98 + <ACUTE ACCENT> 180 190 190 190 194.180 128.99 + <MICRO SIGN> 181 160 160 160 194.181 128.100 + <PARAGRAPH SIGN> 182 182 182 182 194.182 128.101 + <MIDDLE DOT> 183 179 179 179 194.183 128.102 + <CEDILLA> 184 157 157 157 194.184 128.103 + <SUPERSCRIPT ONE> 185 218 218 218 194.185 128.104 + <MASC. ORDINAL INDICATOR> 186 155 155 155 194.186 128.105 + <RIGHT POINTING GUILLEMET> 187 139 139 139 194.187 128.106 + <FRACTION ONE QUARTER> 188 183 183 183 194.188 128.112 + <FRACTION ONE HALF> 189 184 184 184 194.189 128.113 + <FRACTION THREE QUARTERS> 190 185 185 185 194.190 128.114 + <INVERTED QUESTION MARK> 191 171 171 171 194.191 128.115 + <A WITH GRAVE> 192 100 100 100 195.128 138.65 + <A WITH ACUTE> 193 101 101 101 195.129 138.66 + <A WITH CIRCUMFLEX> 194 98 98 98 195.130 138.67 + <A WITH TILDE> 195 102 102 102 195.131 138.68 + <A WITH DIAERESIS> 196 99 99 99 195.132 138.69 + <A WITH RING ABOVE> 197 103 103 103 195.133 138.70 + <CAPITAL LIGATURE AE> 198 158 158 158 195.134 138.71 + <C WITH CEDILLA> 199 104 104 104 195.135 138.72 + <E WITH GRAVE> 200 116 116 116 195.136 138.73 + <E WITH ACUTE> 201 113 113 113 195.137 138.74 + <E WITH CIRCUMFLEX> 202 114 114 114 195.138 138.81 + <E WITH DIAERESIS> 203 115 115 115 195.139 138.82 + <I WITH GRAVE> 204 120 120 120 195.140 138.83 + <I WITH ACUTE> 205 117 117 117 195.141 138.84 + <I WITH CIRCUMFLEX> 206 118 118 118 195.142 138.85 + <I WITH DIAERESIS> 207 119 119 119 195.143 138.86 + <CAPITAL LETTER ETH> 208 172 172 172 195.144 138.87 + <N WITH TILDE> 209 105 105 105 195.145 138.88 + <O WITH GRAVE> 210 237 237 237 195.146 138.89 + <O WITH ACUTE> 211 238 238 238 195.147 138.98 + <O WITH CIRCUMFLEX> 212 235 235 235 195.148 138.99 + <O WITH TILDE> 213 239 239 239 195.149 138.100 + <O WITH DIAERESIS> 214 236 236 236 195.150 138.101 + <MULTIPLICATION SIGN> 215 191 191 191 195.151 138.102 + <O WITH STROKE> 216 128 128 128 195.152 138.103 + <U WITH GRAVE> 217 253 253 224 195.153 138.104 ### + <U WITH ACUTE> 218 254 254 254 195.154 138.105 + <U WITH CIRCUMFLEX> 219 251 251 221 195.155 138.106 ### + <U WITH DIAERESIS> 220 252 252 252 195.156 138.112 + <Y WITH ACUTE> 221 173 186 173 195.157 138.113 *** ### + <CAPITAL LETTER THORN> 222 174 174 174 195.158 138.114 + <SMALL LETTER SHARP S> 223 89 89 89 195.159 138.115 + <a WITH GRAVE> 224 68 68 68 195.160 139.65 + <a WITH ACUTE> 225 69 69 69 195.161 139.66 + <a WITH CIRCUMFLEX> 226 66 66 66 195.162 139.67 + <a WITH TILDE> 227 70 70 70 195.163 139.68 + <a WITH DIAERESIS> 228 67 67 67 195.164 139.69 + <a WITH RING ABOVE> 229 71 71 71 195.165 139.70 + <SMALL LIGATURE ae> 230 156 156 156 195.166 139.71 + <c WITH CEDILLA> 231 72 72 72 195.167 139.72 + <e WITH GRAVE> 232 84 84 84 195.168 139.73 + <e WITH ACUTE> 233 81 81 81 195.169 139.74 + <e WITH CIRCUMFLEX> 234 82 82 82 195.170 139.81 + <e WITH DIAERESIS> 235 83 83 83 195.171 139.82 + <i WITH GRAVE> 236 88 88 88 195.172 139.83 + <i WITH ACUTE> 237 85 85 85 195.173 139.84 + <i WITH CIRCUMFLEX> 238 86 86 86 195.174 139.85 + <i WITH DIAERESIS> 239 87 87 87 195.175 139.86 + <SMALL LETTER eth> 240 140 140 140 195.176 139.87 + <n WITH TILDE> 241 73 73 73 195.177 139.88 + <o WITH GRAVE> 242 205 205 205 195.178 139.89 + <o WITH ACUTE> 243 206 206 206 195.179 139.98 + <o WITH CIRCUMFLEX> 244 203 203 203 195.180 139.99 + <o WITH TILDE> 245 207 207 207 195.181 139.100 + <o WITH DIAERESIS> 246 204 204 204 195.182 139.101 + <DIVISION SIGN> 247 225 225 225 195.183 139.102 + <o WITH STROKE> 248 112 112 112 195.184 139.103 + <u WITH GRAVE> 249 221 221 192 195.185 139.104 ### + <u WITH ACUTE> 250 222 222 222 195.186 139.105 + <u WITH CIRCUMFLEX> 251 219 219 219 195.187 139.106 + <u WITH DIAERESIS> 252 220 220 220 195.188 139.112 + <y WITH ACUTE> 253 141 141 141 195.189 139.113 + <SMALL LETTER thorn> 254 142 142 142 195.190 139.114 + <y WITH DIAERESIS> 255 223 223 223 195.191 139.115 + +If you would rather see the above table in CCSID 0037 order rather than +ASCII + Latin-1 order then run the table through: + +=over 4 + +=item recipe 4 + +=back + + perl -ne 'if(/.{33}\d{1,3}\s{6,8}\d{1,3}\s{6,8}\d{1,3}\s{6,8}\d{1,3}/)'\ + -e '{push(@l,$_)}' \ + -e 'END{print map{$_->[0]}' \ + -e ' sort{$a->[1] <=> $b->[1]}' \ + -e ' map{[$_,substr($_,42,3)]}@l;}' perlebcdic.pod + +If you would rather see it in CCSID 1047 order then change the digit +42 in the last line to 51, like this: + +=over 4 + +=item recipe 5 + +=back + + perl -ne 'if(/.{33}\d{1,3}\s{6,8}\d{1,3}\s{6,8}\d{1,3}\s{6,8}\d{1,3}/)'\ + -e '{push(@l,$_)}' \ + -e 'END{print map{$_->[0]}' \ + -e ' sort{$a->[1] <=> $b->[1]}' \ + -e ' map{[$_,substr($_,51,3)]}@l;}' perlebcdic.pod + +If you would rather see it in POSIX-BC order then change the digit +51 in the last line to 60, like this: + +=over 4 + +=item recipe 6 + +=back + + perl -ne 'if(/.{33}\d{1,3}\s{6,8}\d{1,3}\s{6,8}\d{1,3}\s{6,8}\d{1,3}/)'\ + -e '{push(@l,$_)}' \ + -e 'END{print map{$_->[0]}' \ + -e ' sort{$a->[1] <=> $b->[1]}' \ + -e ' map{[$_,substr($_,60,3)]}@l;}' perlebcdic.pod + + +=head1 IDENTIFYING CHARACTER CODE SETS + +To determine the character set you are running under from perl one +could use the return value of ord() or chr() to test one or more +character values. For example: + + $is_ascii = "A" eq chr(65); + $is_ebcdic = "A" eq chr(193); + +Also, "\t" is a C<HORIZONTAL TABULATION> character so that: + + $is_ascii = ord("\t") == 9; + $is_ebcdic = ord("\t") == 5; + +To distinguish EBCDIC code pages try looking at one or more of +the characters that differ between them. For example: + + $is_ebcdic_37 = "\n" eq chr(37); + $is_ebcdic_1047 = "\n" eq chr(21); + +Or better still choose a character that is uniquely encoded in any +of the code sets, e.g.: + + $is_ascii = ord('[') == 91; + $is_ebcdic_37 = ord('[') == 186; + $is_ebcdic_1047 = ord('[') == 173; + $is_ebcdic_POSIX_BC = ord('[') == 187; + +However, it would be unwise to write tests such as: + + $is_ascii = "\r" ne chr(13); # WRONG + $is_ascii = "\n" ne chr(10); # ILL ADVISED + +Obviously the first of these will fail to distinguish most ASCII platforms +from either a CCSID 0037, a 1047, or a POSIX-BC EBCDIC platform since "\r" eq +chr(13) under all of those coded character sets. But note too that +because "\n" is chr(13) and "\r" is chr(10) on the MacIntosh (which is an +ASCII platform) the second C<$is_ascii> test will lead to trouble there. + +To determine whether or not perl was built under an EBCDIC +code page you can use the Config module like so: + + use Config; + $is_ebcdic = $Config{'ebcdic'} eq 'define'; + +=head1 CONVERSIONS + +=head2 tr/// + +In order to convert a string of characters from one character set to +another a simple list of numbers, such as in the right columns in the +above table, along with perl's tr/// operator is all that is needed. +The data in the table are in ASCII order hence the EBCDIC columns +provide easy to use ASCII to EBCDIC operations that are also easily +reversed. + +For example, to convert ASCII to code page 037 take the output of the second +column from the output of recipe 0 (modified to add \\ characters) and use +it in tr/// like so: + + $cp_037 = + '\000\001\002\003\234\011\206\177\227\215\216\013\014\015\016\017' . + '\020\021\022\023\235\205\010\207\030\031\222\217\034\035\036\037' . + '\200\201\202\203\204\012\027\033\210\211\212\213\214\005\006\007' . + '\220\221\026\223\224\225\226\004\230\231\232\233\024\025\236\032' . + '\040\240\342\344\340\341\343\345\347\361\242\056\074\050\053\174' . + '\046\351\352\353\350\355\356\357\354\337\041\044\052\051\073\254' . + '\055\057\302\304\300\301\303\305\307\321\246\054\045\137\076\077' . + '\370\311\312\313\310\315\316\317\314\140\072\043\100\047\075\042' . + '\330\141\142\143\144\145\146\147\150\151\253\273\360\375\376\261' . + '\260\152\153\154\155\156\157\160\161\162\252\272\346\270\306\244' . + '\265\176\163\164\165\166\167\170\171\172\241\277\320\335\336\256' . + '\136\243\245\267\251\247\266\274\275\276\133\135\257\250\264\327' . + '\173\101\102\103\104\105\106\107\110\111\255\364\366\362\363\365' . + '\175\112\113\114\115\116\117\120\121\122\271\373\374\371\372\377' . + '\134\367\123\124\125\126\127\130\131\132\262\324\326\322\323\325' . + '\060\061\062\063\064\065\066\067\070\071\263\333\334\331\332\237' ; + + my $ebcdic_string = $ascii_string; + eval '$ebcdic_string =~ tr/' . $cp_037 . '/\000-\377/'; + +To convert from EBCDIC 037 to ASCII just reverse the order of the tr/// +arguments like so: + + my $ascii_string = $ebcdic_string; + eval '$ascii_string =~ tr/\000-\377/' . $cp_037 . '/'; + +Similarly one could take the output of the third column from recipe 0 to +obtain a C<$cp_1047> table. The fourth column of the output from recipe +0 could provide a C<$cp_posix_bc> table suitable for transcoding as well. + +=head2 iconv + +XPG operability often implies the presence of an I<iconv> utility +available from the shell or from the C library. Consult your system's +documentation for information on iconv. + +On OS/390 or z/OS see the iconv(1) manpage. One way to invoke the iconv +shell utility from within perl would be to: + + # OS/390 or z/OS example + $ascii_data = `echo '$ebcdic_data'| iconv -f IBM-1047 -t ISO8859-1` + +or the inverse map: + + # OS/390 or z/OS example + $ebcdic_data = `echo '$ascii_data'| iconv -f ISO8859-1 -t IBM-1047` + +For other perl based conversion options see the Convert::* modules on CPAN. + +=head2 C RTL + +The OS/390 and z/OS C run time libraries provide _atoe() and _etoa() functions. + +=head1 OPERATOR DIFFERENCES + +The C<..> range operator treats certain character ranges with +care on EBCDIC platforms. For example the following array +will have twenty six elements on either an EBCDIC platform +or an ASCII platform: + + @alphabet = ('A'..'Z'); # $#alphabet == 25 + +The bitwise operators such as & ^ | may return different results +when operating on string or character data in a perl program running +on an EBCDIC platform than when run on an ASCII platform. Here is +an example adapted from the one in L<perlop>: + + # EBCDIC-based examples + print "j p \n" ^ " a h"; # prints "JAPH\n" + print "JA" | " ph\n"; # prints "japh\n" + print "JAPH\nJunk" & "\277\277\277\277\277"; # prints "japh\n"; + print 'p N$' ^ " E<H\n"; # prints "Perl\n"; + +An interesting property of the 32 C0 control characters +in the ASCII table is that they can "literally" be constructed +as control characters in perl, e.g. C<(chr(0) eq "\c@")> +C<(chr(1) eq "\cA")>, and so on. Perl on EBCDIC platforms has been +ported to take "\c@" to chr(0) and "\cA" to chr(1) as well, but the +thirty three characters that result depend on which code page you are +using. The table below uses the character names from the previous table +but with substitutions such as s/START OF/S.O./; s/END OF /E.O./; +s/TRANSMISSION/TRANS./; s/TABULATION/TAB./; s/VERTICAL/VERT./; +s/HORIZONTAL/HORIZ./; s/DEVICE CONTROL/D.C./; s/SEPARATOR/SEP./; +s/NEGATIVE ACKNOWLEDGE/NEG. ACK./;. The POSIX-BC and 1047 sets are +identical throughout this range and differ from the 0037 set at only +one spot (21 decimal). Note that the C<LINE FEED> character +may be generated by "\cJ" on ASCII platforms but by "\cU" on 1047 or POSIX-BC +platforms and cannot be generated as a C<"\c.letter."> control character on +0037 platforms. Note also that "\c\\" maps to two characters +not one. + + chr ord 8859-1 0037 1047 && POSIX-BC + ------------------------------------------------------------------------ + "\c?" 127 <DELETE> " " ***>< + "\c@" 0 <NULL> <NULL> <NULL> ***>< + "\cA" 1 <S.O. HEADING> <S.O. HEADING> <S.O. HEADING> + "\cB" 2 <S.O. TEXT> <S.O. TEXT> <S.O. TEXT> + "\cC" 3 <E.O. TEXT> <E.O. TEXT> <E.O. TEXT> + "\cD" 4 <E.O. TRANS.> <C1 28> <C1 28> + "\cE" 5 <ENQUIRY> <HORIZ. TAB.> <HORIZ. TAB.> + "\cF" 6 <ACKNOWLEDGE> <C1 6> <C1 6> + "\cG" 7 <BELL> <DELETE> <DELETE> + "\cH" 8 <BACKSPACE> <C1 23> <C1 23> + "\cI" 9 <HORIZ. TAB.> <C1 13> <C1 13> + "\cJ" 10 <LINE FEED> <C1 14> <C1 14> + "\cK" 11 <VERT. TAB.> <VERT. TAB.> <VERT. TAB.> + "\cL" 12 <FORM FEED> <FORM FEED> <FORM FEED> + "\cM" 13 <CARRIAGE RETURN> <CARRIAGE RETURN> <CARRIAGE RETURN> + "\cN" 14 <SHIFT OUT> <SHIFT OUT> <SHIFT OUT> + "\cO" 15 <SHIFT IN> <SHIFT IN> <SHIFT IN> + "\cP" 16 <DATA LINK ESCAPE> <DATA LINK ESCAPE> <DATA LINK ESCAPE> + "\cQ" 17 <D.C. ONE> <D.C. ONE> <D.C. ONE> + "\cR" 18 <D.C. TWO> <D.C. TWO> <D.C. TWO> + "\cS" 19 <D.C. THREE> <D.C. THREE> <D.C. THREE> + "\cT" 20 <D.C. FOUR> <C1 29> <C1 29> + "\cU" 21 <NEG. ACK.> <C1 5> <LINE FEED> *** + "\cV" 22 <SYNCHRONOUS IDLE> <BACKSPACE> <BACKSPACE> + "\cW" 23 <E.O. TRANS. BLOCK> <C1 7> <C1 7> + "\cX" 24 <CANCEL> <CANCEL> <CANCEL> + "\cY" 25 <E.O. MEDIUM> <E.O. MEDIUM> <E.O. MEDIUM> + "\cZ" 26 <SUBSTITUTE> <C1 18> <C1 18> + "\c[" 27 <ESCAPE> <C1 15> <C1 15> + "\c\\" 28 <FILE SEP.>\ <FILE SEP.>\ <FILE SEP.>\ + "\c]" 29 <GROUP SEP.> <GROUP SEP.> <GROUP SEP.> + "\c^" 30 <RECORD SEP.> <RECORD SEP.> <RECORD SEP.> ***>< + "\c_" 31 <UNIT SEP.> <UNIT SEP.> <UNIT SEP.> ***>< + + +=head1 FUNCTION DIFFERENCES + +=over 8 + +=item chr() + +chr() must be given an EBCDIC code number argument to yield a desired +character return value on an EBCDIC platform. For example: + + $CAPITAL_LETTER_A = chr(193); + +=item ord() + +ord() will return EBCDIC code number values on an EBCDIC platform. +For example: + + $the_number_193 = ord("A"); + +=item pack() + +The c and C templates for pack() are dependent upon character set +encoding. Examples of usage on EBCDIC include: + + $foo = pack("CCCC",193,194,195,196); + # $foo eq "ABCD" + $foo = pack("C4",193,194,195,196); + # same thing + + $foo = pack("ccxxcc",193,194,195,196); + # $foo eq "AB\0\0CD" + +=item print() + +One must be careful with scalars and strings that are passed to +print that contain ASCII encodings. One common place +for this to occur is in the output of the MIME type header for +CGI script writing. For example, many perl programming guides +recommend something similar to: + + print "Content-type:\ttext/html\015\012\015\012"; + # this may be wrong on EBCDIC + +Under the IBM OS/390 USS Web Server or WebSphere on z/OS for example +you should instead write that as: + + print "Content-type:\ttext/html\r\n\r\n"; # OK for DGW et alia + +That is because the translation from EBCDIC to ASCII is done +by the web server in this case (such code will not be appropriate for +the Macintosh however). Consult your web server's documentation for +further details. + +=item printf() + +The formats that can convert characters to numbers and vice versa +will be different from their ASCII counterparts when executed +on an EBCDIC platform. Examples include: + + printf("%c%c%c",193,194,195); # prints ABC + +=item sort() + +EBCDIC sort results may differ from ASCII sort results especially for +mixed case strings. This is discussed in more detail below. + +=item sprintf() + +See the discussion of printf() above. An example of the use +of sprintf would be: + + $CAPITAL_LETTER_A = sprintf("%c",193); + +=item unpack() + +See the discussion of pack() above. + +=back + +=head1 REGULAR EXPRESSION DIFFERENCES + +As of perl 5.005_03 the letter range regular expression such as +[A-Z] and [a-z] have been especially coded to not pick up gap +characters. For example, characters such as E<ocirc> C<o WITH CIRCUMFLEX> +that lie between I and J would not be matched by the +regular expression range C</[H-K]/>. This works in +the other direction, too, if either of the range end points is +explicitly numeric: C<[\x89-\x91]> will match C<\x8e>, even +though C<\x89> is C<i> and C<\x91 > is C<j>, and C<\x8e> +is a gap character from the alphabetic viewpoint. + +If you do want to match the alphabet gap characters in a single octet +regular expression try matching the hex or octal code such +as C</\313/> on EBCDIC or C</\364/> on ASCII platforms to +have your regular expression match C<o WITH CIRCUMFLEX>. + +Another construct to be wary of is the inappropriate use of hex or +octal constants in regular expressions. Consider the following +set of subs: + + sub is_c0 { + my $char = substr(shift,0,1); + $char =~ /[\000-\037]/; + } + + sub is_print_ascii { + my $char = substr(shift,0,1); + $char =~ /[\040-\176]/; + } + + sub is_delete { + my $char = substr(shift,0,1); + $char eq "\177"; + } + + sub is_c1 { + my $char = substr(shift,0,1); + $char =~ /[\200-\237]/; + } + + sub is_latin_1 { + my $char = substr(shift,0,1); + $char =~ /[\240-\377]/; + } + +The above would be adequate if the concern was only with numeric code points. +However, the concern may be with characters rather than code points +and on an EBCDIC platform it may be desirable for constructs such as +C<if (is_print_ascii("A")) {print "A is a printable character\n";}> to print +out the expected message. One way to represent the above collection +of character classification subs that is capable of working across the +four coded character sets discussed in this document is as follows: + + sub Is_c0 { + my $char = substr(shift,0,1); + if (ord('^')==94) { # ascii + return $char =~ /[\000-\037]/; + } + if (ord('^')==176) { # 37 + return $char =~ /[\000-\003\067\055-\057\026\005\045\013-\023\074\075\062\046\030\031\077\047\034-\037]/; + } + if (ord('^')==95 || ord('^')==106) { # 1047 || posix-bc + return $char =~ /[\000-\003\067\055-\057\026\005\025\013-\023\074\075\062\046\030\031\077\047\034-\037]/; + } + } + + sub Is_print_ascii { + my $char = substr(shift,0,1); + $char =~ /[ !"\#\$%&'()*+,\-.\/0-9:;<=>?\@A-Z[\\\]^_`a-z{|}~]/; + } + + sub Is_delete { + my $char = substr(shift,0,1); + if (ord('^')==94) { # ascii + return $char eq "\177"; + } + else { # ebcdic + return $char eq "\007"; + } + } + + sub Is_c1 { + my $char = substr(shift,0,1); + if (ord('^')==94) { # ascii + return $char =~ /[\200-\237]/; + } + if (ord('^')==176) { # 37 + return $char =~ /[\040-\044\025\006\027\050-\054\011\012\033\060\061\032\063-\066\010\070-\073\040\024\076\377]/; + } + if (ord('^')==95) { # 1047 + return $char =~ /[\040-\045\006\027\050-\054\011\012\033\060\061\032\063-\066\010\070-\073\040\024\076\377]/; + } + if (ord('^')==106) { # posix-bc + return $char =~ + /[\040-\045\006\027\050-\054\011\012\033\060\061\032\063-\066\010\070-\073\040\024\076\137]/; + } + } + + sub Is_latin_1 { + my $char = substr(shift,0,1); + if (ord('^')==94) { # ascii + return $char =~ /[\240-\377]/; + } + if (ord('^')==176) { # 37 + return $char =~ + /[\101\252\112\261\237\262\152\265\275\264\232\212\137\312\257\274\220\217\352\372\276\240\266\263\235\332\233\213\267\270\271\253\144\145\142\146\143\147\236\150\164\161-\163\170\165-\167\254\151\355\356\353\357\354\277\200\375\376\373\374\255\256\131\104\105\102\106\103\107\234\110\124\121-\123\130\125-\127\214\111\315\316\313\317\314\341\160\335\336\333\334\215\216\337]/; + } + if (ord('^')==95) { # 1047 + return $char =~ + /[\101\252\112\261\237\262\152\265\273\264\232\212\260\312\257\274\220\217\352\372\276\240\266\263\235\332\233\213\267\270\271\253\144\145\142\146\143\147\236\150\164\161-\163\170\165-\167\254\151\355\356\353\357\354\277\200\375\376\373\374\272\256\131\104\105\102\106\103\107\234\110\124\121-\123\130\125-\127\214\111\315\316\313\317\314\341\160\335\336\333\334\215\216\337]/; + } + if (ord('^')==106) { # posix-bc + return $char =~ + /[\101\252\260\261\237\262\320\265\171\264\232\212\272\312\257\241\220\217\352\372\276\240\266\263\235\332\233\213\267\270\271\253\144\145\142\146\143\147\236\150\164\161-\163\170\165-\167\254\151\355\356\353\357\354\277\200\340\376\335\374\255\256\131\104\105\102\106\103\107\234\110\124\121-\123\130\125-\127\214\111\315\316\313\317\314\341\160\300\336\333\334\215\216\337]/; + } + } + +Note however that only the C<Is_ascii_print()> sub is really independent +of coded character set. Another way to write C<Is_latin_1()> would be +to use the characters in the range explicitly: + + sub Is_latin_1 { + my $char = substr(shift,0,1); + $char =~ /[ ¡¢£¤¥¦§¨©ª«¬®¯°±²³´µ¶·¸¹º»¼½¾¿ÀÁÂÃÄÅÆÇÈÉÊËÌÍÎÏÐÑÒÓÔÕÖ×ØÙÚÛÜÝÞßàáâãäåæçèéêëìíîïðñòóôõö÷øùúûüýþÿ]/; + } + +Although that form may run into trouble in network transit (due to the +presence of 8 bit characters) or on non ISO-Latin character sets. + +=head1 SOCKETS + +Most socket programming assumes ASCII character encodings in network +byte order. Exceptions can include CGI script writing under a +host web server where the server may take care of translation for you. +Most host web servers convert EBCDIC data to ISO-8859-1 or Unicode on +output. + +=head1 SORTING + +One big difference between ASCII based character sets and EBCDIC ones +are the relative positions of upper and lower case letters and the +letters compared to the digits. If sorted on an ASCII based platform the +two letter abbreviation for a physician comes before the two letter +for drive, that is: + + @sorted = sort(qw(Dr. dr.)); # @sorted holds ('Dr.','dr.') on ASCII, + # but ('dr.','Dr.') on EBCDIC + +The property of lower case before uppercase letters in EBCDIC is +even carried to the Latin 1 EBCDIC pages such as 0037 and 1047. +An example would be that E<Euml> C<E WITH DIAERESIS> (203) comes +before E<euml> C<e WITH DIAERESIS> (235) on an ASCII platform, but +the latter (83) comes before the former (115) on an EBCDIC platform. +(Astute readers will note that the upper case version of E<szlig> +C<SMALL LETTER SHARP S> is simply "SS" and that the upper case version of +E<yuml> C<y WITH DIAERESIS> is not in the 0..255 range but it is +at U+x0178 in Unicode, or C<"\x{178}"> in a Unicode enabled Perl). + +The sort order will cause differences between results obtained on +ASCII platforms versus EBCDIC platforms. What follows are some suggestions +on how to deal with these differences. + +=head2 Ignore ASCII vs. EBCDIC sort differences. + +This is the least computationally expensive strategy. It may require +some user education. + +=head2 MONO CASE then sort data. + +In order to minimize the expense of mono casing mixed test try to +C<tr///> towards the character set case most employed within the data. +If the data are primarily UPPERCASE non Latin 1 then apply tr/[a-z]/[A-Z]/ +then sort(). If the data are primarily lowercase non Latin 1 then +apply tr/[A-Z]/[a-z]/ before sorting. If the data are primarily UPPERCASE +and include Latin-1 characters then apply: + + tr/[a-z]/[A-Z]/; + tr/[àáâãäåæçèéêëìíîïðñòóôõöøùúûüýþ]/[ÀÁÂÃÄÅÆÇÈÉÊËÌÍÎÏÐÑÒÓÔÕÖØÙÚÛÜÝÞ]/; + s/ß/SS/g; + +then sort(). Do note however that such Latin-1 manipulation does not +address the E<yuml> C<y WITH DIAERESIS> character that will remain at +code point 255 on ASCII platforms, but 223 on most EBCDIC platforms +where it will sort to a place less than the EBCDIC numerals. With a +Unicode enabled Perl you might try: + + tr/^?/\x{178}/; + +The strategy of mono casing data before sorting does not preserve the case +of the data and may not be acceptable for that reason. + +=head2 Convert, sort data, then re convert. + +This is the most expensive proposition that does not employ a network +connection. + +=head2 Perform sorting on one type of platform only. + +This strategy can employ a network connection. As such +it would be computationally expensive. + +=head1 TRANSFORMATION FORMATS + +There are a variety of ways of transforming data with an intra character set +mapping that serve a variety of purposes. Sorting was discussed in the +previous section and a few of the other more popular mapping techniques are +discussed next. + +=head2 URL decoding and encoding + +Note that some URLs have hexadecimal ASCII code points in them in an +attempt to overcome character or protocol limitation issues. For example +the tilde character is not on every keyboard hence a URL of the form: + + http://www.pvhp.com/~pvhp/ + +may also be expressed as either of: + + http://www.pvhp.com/%7Epvhp/ + + http://www.pvhp.com/%7epvhp/ + +where 7E is the hexadecimal ASCII code point for '~'. Here is an example +of decoding such a URL under CCSID 1047: + + $url = 'http://www.pvhp.com/%7Epvhp/'; + # this array assumes code page 1047 + my @a2e_1047 = ( + 0, 1, 2, 3, 55, 45, 46, 47, 22, 5, 21, 11, 12, 13, 14, 15, + 16, 17, 18, 19, 60, 61, 50, 38, 24, 25, 63, 39, 28, 29, 30, 31, + 64, 90,127,123, 91,108, 80,125, 77, 93, 92, 78,107, 96, 75, 97, + 240,241,242,243,244,245,246,247,248,249,122, 94, 76,126,110,111, + 124,193,194,195,196,197,198,199,200,201,209,210,211,212,213,214, + 215,216,217,226,227,228,229,230,231,232,233,173,224,189, 95,109, + 121,129,130,131,132,133,134,135,136,137,145,146,147,148,149,150, + 151,152,153,162,163,164,165,166,167,168,169,192, 79,208,161, 7, + 32, 33, 34, 35, 36, 37, 6, 23, 40, 41, 42, 43, 44, 9, 10, 27, + 48, 49, 26, 51, 52, 53, 54, 8, 56, 57, 58, 59, 4, 20, 62,255, + 65,170, 74,177,159,178,106,181,187,180,154,138,176,202,175,188, + 144,143,234,250,190,160,182,179,157,218,155,139,183,184,185,171, + 100,101, 98,102, 99,103,158,104,116,113,114,115,120,117,118,119, + 172,105,237,238,235,239,236,191,128,253,254,251,252,186,174, 89, + 68, 69, 66, 70, 67, 71,156, 72, 84, 81, 82, 83, 88, 85, 86, 87, + 140, 73,205,206,203,207,204,225,112,221,222,219,220,141,142,223 + ); + $url =~ s/%([0-9a-fA-F]{2})/pack("c",$a2e_1047[hex($1)])/ge; + +Conversely, here is a partial solution for the task of encoding such +a URL under the 1047 code page: + + $url = 'http://www.pvhp.com/~pvhp/'; + # this array assumes code page 1047 + my @e2a_1047 = ( + 0, 1, 2, 3,156, 9,134,127,151,141,142, 11, 12, 13, 14, 15, + 16, 17, 18, 19,157, 10, 8,135, 24, 25,146,143, 28, 29, 30, 31, + 128,129,130,131,132,133, 23, 27,136,137,138,139,140, 5, 6, 7, + 144,145, 22,147,148,149,150, 4,152,153,154,155, 20, 21,158, 26, + 32,160,226,228,224,225,227,229,231,241,162, 46, 60, 40, 43,124, + 38,233,234,235,232,237,238,239,236,223, 33, 36, 42, 41, 59, 94, + 45, 47,194,196,192,193,195,197,199,209,166, 44, 37, 95, 62, 63, + 248,201,202,203,200,205,206,207,204, 96, 58, 35, 64, 39, 61, 34, + 216, 97, 98, 99,100,101,102,103,104,105,171,187,240,253,254,177, + 176,106,107,108,109,110,111,112,113,114,170,186,230,184,198,164, + 181,126,115,116,117,118,119,120,121,122,161,191,208, 91,222,174, + 172,163,165,183,169,167,182,188,189,190,221,168,175, 93,180,215, + 123, 65, 66, 67, 68, 69, 70, 71, 72, 73,173,244,246,242,243,245, + 125, 74, 75, 76, 77, 78, 79, 80, 81, 82,185,251,252,249,250,255, + 92,247, 83, 84, 85, 86, 87, 88, 89, 90,178,212,214,210,211,213, + 48, 49, 50, 51, 52, 53, 54, 55, 56, 57,179,219,220,217,218,159 + ); + # The following regular expression does not address the + # mappings for: ('.' => '%2E', '/' => '%2F', ':' => '%3A') + $url =~ s/([\t "#%&\(\),;<=>\?\@\[\\\]^`{|}~])/sprintf("%%%02X",$e2a_1047[ord($1)])/ge; + +where a more complete solution would split the URL into components +and apply a full s/// substitution only to the appropriate parts. + +In the remaining examples a @e2a or @a2e array may be employed +but the assignment will not be shown explicitly. For code page 1047 +you could use the @a2e_1047 or @e2a_1047 arrays just shown. + +=head2 uu encoding and decoding + +The C<u> template to pack() or unpack() will render EBCDIC data in EBCDIC +characters equivalent to their ASCII counterparts. For example, the +following will print "Yes indeed\n" on either an ASCII or EBCDIC computer: + + $all_byte_chrs = ''; + for (0..255) { $all_byte_chrs .= chr($_); } + $uuencode_byte_chrs = pack('u', $all_byte_chrs); + ($uu = <<'ENDOFHEREDOC') =~ s/^\s*//gm; + M``$"`P0%!@<("0H+#`T.#Q`1$A,4%187&!D:&QP='A\@(2(C)"4F)R@I*BLL + M+2XO,#$R,S0U-C<X.3H[/#T^/T!!0D-$149'2$E*2TQ-3D]045)35%565UA9 + M6EM<75Y?8&%B8V1E9F=H:6IK;&UN;W!Q<G-T=79W>'EZ>WQ]?G^`@8*#A(6& + MAXB)BHN,C8Z/D)&2DY25EI>8F9J;G)V>GZ"AHJ.DI::GJ*FJJZRMKJ^PL;*S + MM+6VM[BYNKN\O;Z_P,'"P\3%QL?(R<K+S,W.S]#1TM/4U=;7V-G:V]S=WM_@ + ?X>+CY.7FY^CIZNOL[>[O\/'R\_3U]O?X^?K[_/W^_P`` + ENDOFHEREDOC + if ($uuencode_byte_chrs eq $uu) { + print "Yes "; + } + $uudecode_byte_chrs = unpack('u', $uuencode_byte_chrs); + if ($uudecode_byte_chrs eq $all_byte_chrs) { + print "indeed\n"; + } + +Here is a very spartan uudecoder that will work on EBCDIC provided +that the @e2a array is filled in appropriately: + + #!/usr/local/bin/perl + @e2a = ( # this must be filled in + ); + $_ = <> until ($mode,$file) = /^begin\s*(\d*)\s*(\S*)/; + open(OUT, "> $file") if $file ne ""; + while(<>) { + last if /^end/; + next if /[a-z]/; + next unless int(((($e2a[ord()] - 32 ) & 077) + 2) / 3) == + int(length() / 4); + print OUT unpack("u", $_); + } + close(OUT); + chmod oct($mode), $file; + + +=head2 Quoted-Printable encoding and decoding + +On ASCII encoded platforms it is possible to strip characters outside of +the printable set using: + + # This QP encoder works on ASCII only + $qp_string =~ s/([=\x00-\x1F\x80-\xFF])/sprintf("=%02X",ord($1))/ge; + +Whereas a QP encoder that works on both ASCII and EBCDIC platforms +would look somewhat like the following (where the EBCDIC branch @e2a +array is omitted for brevity): + + if (ord('A') == 65) { # ASCII + $delete = "\x7F"; # ASCII + @e2a = (0 .. 255) # ASCII to ASCII identity map + } + else { # EBCDIC + $delete = "\x07"; # EBCDIC + @e2a = # EBCDIC to ASCII map (as shown above) + } + $qp_string =~ + s/([^ !"\#\$%&'()*+,\-.\/0-9:;<>?\@A-Z[\\\]^_`a-z{|}~$delete])/sprintf("=%02X",$e2a[ord($1)])/ge; + +(although in production code the substitutions might be done +in the EBCDIC branch with the @e2a array and separately in the +ASCII branch without the expense of the identity map). + +Such QP strings can be decoded with: + + # This QP decoder is limited to ASCII only + $string =~ s/=([0-9A-Fa-f][0-9A-Fa-f])/chr hex $1/ge; + $string =~ s/=[\n\r]+$//; + +Whereas a QP decoder that works on both ASCII and EBCDIC platforms +would look somewhat like the following (where the @a2e array is +omitted for brevity): + + $string =~ s/=([0-9A-Fa-f][0-9A-Fa-f])/chr $a2e[hex $1]/ge; + $string =~ s/=[\n\r]+$//; + +=head2 Caesarian ciphers + +The practice of shifting an alphabet one or more characters for encipherment +dates back thousands of years and was explicitly detailed by Gaius Julius +Caesar in his B<Gallic Wars> text. A single alphabet shift is sometimes +referred to as a rotation and the shift amount is given as a number $n after +the string 'rot' or "rot$n". Rot0 and rot26 would designate identity maps +on the 26 letter English version of the Latin alphabet. Rot13 has the +interesting property that alternate subsequent invocations are identity maps +(thus rot13 is its own non-trivial inverse in the group of 26 alphabet +rotations). Hence the following is a rot13 encoder and decoder that will +work on ASCII and EBCDIC platforms: + + #!/usr/local/bin/perl + + while(<>){ + tr/n-za-mN-ZA-M/a-zA-Z/; + print; + } + +In one-liner form: + + perl -ne 'tr/n-za-mN-ZA-M/a-zA-Z/;print' + + +=head1 Hashing order and checksums + +To the extent that it is possible to write code that depends on +hashing order there may be differences between hashes as stored +on an ASCII based platform and hashes stored on an EBCDIC based platform. +XXX + +=head1 I18N AND L10N + +Internationalization(I18N) and localization(L10N) are supported at least +in principle even on EBCDIC platforms. The details are system dependent +and discussed under the L<perlebcdic/OS ISSUES> section below. + +=head1 MULTI OCTET CHARACTER SETS + +Perl may work with an internal UTF-EBCDIC encoding form for wide characters +on EBCDIC platforms in a manner analogous to the way that it works with +the UTF-8 internal encoding form on ASCII based platforms. + +Legacy multi byte EBCDIC code pages XXX. + +=head1 OS ISSUES + +There may be a few system dependent issues +of concern to EBCDIC Perl programmers. + +=head2 OS/400 + +=over 8 + +=item PASE + +The PASE environment is runtime environment for OS/400 that can run +executables built for PowerPC AIX in OS/400, see L<perlos400>. PASE +is ASCII-based, not EBCDIC-based as the ILE. + +=item IFS access + +XXX. + +=back + +=head2 OS/390, z/OS + +Perl runs under Unix Systems Services or USS. + +=over 8 + +=item chcp + +B<chcp> is supported as a shell utility for displaying and changing +one's code page. See also L<chcp>. + +=item dataset access + +For sequential data set access try: + + my @ds_records = `cat //DSNAME`; + +or: + + my @ds_records = `cat //'HLQ.DSNAME'`; + +See also the OS390::Stdio module on CPAN. + +=item OS/390, z/OS iconv + +B<iconv> is supported as both a shell utility and a C RTL routine. +See also the iconv(1) and iconv(3) manual pages. + +=item locales + +On OS/390 or z/OS see L<locale> for information on locales. The L10N files +are in F</usr/nls/locale>. $Config{d_setlocale} is 'define' on OS/390 +or z/OS. + +=back + +=head2 VM/ESA? + +XXX. + +=head2 POSIX-BC? + +XXX. + +=head1 BUGS + +This pod document contains literal Latin 1 characters and may encounter +translation difficulties. In particular one popular nroff implementation +was known to strip accented characters to their unaccented counterparts +while attempting to view this document through the B<pod2man> program +(for example, you may see a plain C<y> rather than one with a diaeresis +as in E<yuml>). Another nroff truncated the resultant manpage at +the first occurrence of 8 bit characters. + +Not all shells will allow multiple C<-e> string arguments to perl to +be concatenated together properly as recipes 0, 2, 4, 5, and 6 might +seem to imply. + +=head1 SEE ALSO + +L<perllocale>, L<perlfunc>, L<perlunicode>, L<utf8>. + +=head1 REFERENCES + +L<http://anubis.dkuug.dk/i18n/charmaps> + +L<http://www.unicode.org/> + +L<http://www.unicode.org/unicode/reports/tr16/> + +L<http://www.wps.com/texts/codes/> +B<ASCII: American Standard Code for Information Infiltration> Tom Jennings, +September 1999. + +B<The Unicode Standard, Version 3.0> The Unicode Consortium, Lisa Moore ed., +ISBN 0-201-61633-5, Addison Wesley Developers Press, February 2000. + +B<CDRA: IBM - Character Data Representation Architecture - +Reference and Registry>, IBM SC09-2190-00, December 1996. + +"Demystifying Character Sets", Andrea Vine, Multilingual Computing +& Technology, B<#26 Vol. 10 Issue 4>, August/September 1999; +ISSN 1523-0309; Multilingual Computing Inc. Sandpoint ID, USA. + +B<Codes, Ciphers, and Other Cryptic and Clandestine Communication> +Fred B. Wrixon, ISBN 1-57912-040-7, Black Dog & Leventhal Publishers, +1998. + +L<http://www.bobbemer.com/P-BIT.HTM> +B<IBM - EBCDIC and the P-bit; The biggest Computer Goof Ever> Robert Bemer. + +=head1 HISTORY + +15 April 2001: added UTF-8 and UTF-EBCDIC to main table, pvhp. + +=head1 AUTHOR + +Peter Prymmer pvhp@best.com wrote this in 1999 and 2000 +with CCSID 0819 and 0037 help from Chris Leach and +AndrE<eacute> Pirard A.Pirard@ulg.ac.be as well as POSIX-BC +help from Thomas Dorner Thomas.Dorner@start.de. +Thanks also to Vickie Cooper, Philip Newton, William Raffloer, and +Joe Smith. Trademarks, registered trademarks, service marks and +registered service marks used in this document are the property of +their respective owners. + + |