| 1 | =head1 NAME |
| 2 | |
| 3 | perlebcdic - Considerations for running Perl on EBCDIC platforms |
| 4 | |
| 5 | =head1 DESCRIPTION |
| 6 | |
| 7 | An exploration of some of the issues facing Perl programmers |
| 8 | on EBCDIC based computers. We do not cover localization, |
| 9 | internationalization, or multi byte character set issues other |
| 10 | than some discussion of UTF-8 and UTF-EBCDIC. |
| 11 | |
| 12 | Portions that are still incomplete are marked with XXX. |
| 13 | |
| 14 | =head1 COMMON CHARACTER CODE SETS |
| 15 | |
| 16 | =head2 ASCII |
| 17 | |
| 18 | The American Standard Code for Information Interchange is a set of |
| 19 | integers running from 0 to 127 (decimal) that imply character |
| 20 | interpretation by the display and other system(s) of computers. |
| 21 | The range 0..127 can be covered by setting the bits in a 7-bit binary |
| 22 | digit, hence the set is sometimes referred to as a "7-bit ASCII". |
| 23 | ASCII was described by the American National Standards Institute |
| 24 | document ANSI X3.4-1986. It was also described by ISO 646:1991 |
| 25 | (with localization for currency symbols). The full ASCII set is |
| 26 | given in the table below as the first 128 elements. Languages that |
| 27 | can be written adequately with the characters in ASCII include |
| 28 | English, Hawaiian, Indonesian, Swahili and some Native American |
| 29 | languages. |
| 30 | |
| 31 | There are many character sets that extend the range of integers |
| 32 | from 0..2**7-1 up to 2**8-1, or 8 bit bytes (octets if you prefer). |
| 33 | One common one is the ISO 8859-1 character set. |
| 34 | |
| 35 | =head2 ISO 8859 |
| 36 | |
| 37 | The ISO 8859-$n are a collection of character code sets from the |
| 38 | International Organization for Standardization (ISO) each of which |
| 39 | adds characters to the ASCII set that are typically found in European |
| 40 | languages many of which are based on the Roman, or Latin, alphabet. |
| 41 | |
| 42 | =head2 Latin 1 (ISO 8859-1) |
| 43 | |
| 44 | A particular 8-bit extension to ASCII that includes grave and acute |
| 45 | accented Latin characters. Languages that can employ ISO 8859-1 |
| 46 | include all the languages covered by ASCII as well as Afrikaans, |
| 47 | Albanian, Basque, Catalan, Danish, Faroese, Finnish, Norwegian, |
| 48 | Portuguese, Spanish, and Swedish. Dutch is covered albeit without |
| 49 | the ij ligature. French is covered too but without the oe ligature. |
| 50 | German can use ISO 8859-1 but must do so without German-style |
| 51 | quotation marks. This set is based on Western European extensions |
| 52 | to ASCII and is commonly encountered in world wide web work. |
| 53 | In IBM character code set identification terminology ISO 8859-1 is |
| 54 | also known as CCSID 819 (or sometimes 0819 or even 00819). |
| 55 | |
| 56 | =head2 EBCDIC |
| 57 | |
| 58 | The Extended Binary Coded Decimal Interchange Code refers to a |
| 59 | large collection of slightly different single and multi byte |
| 60 | coded character sets that are different from ASCII or ISO 8859-1 |
| 61 | and typically run on host computers. The EBCDIC encodings derive |
| 62 | from 8 bit byte extensions of Hollerith punched card encodings. |
| 63 | The layout on the cards was such that high bits were set for the |
| 64 | upper and lower case alphabet characters [a-z] and [A-Z], but there |
| 65 | were gaps within each latin alphabet range. |
| 66 | |
| 67 | Some IBM EBCDIC character sets may be known by character code set |
| 68 | identification numbers (CCSID numbers) or code page numbers. Leading |
| 69 | zero digits in CCSID numbers within this document are insignificant. |
| 70 | E.g. CCSID 0037 may be referred to as 37 in places. |
| 71 | |
| 72 | =head2 13 variant characters |
| 73 | |
| 74 | Among IBM EBCDIC character code sets there are 13 characters that |
| 75 | are often mapped to different integer values. Those characters |
| 76 | are known as the 13 "variant" characters and are: |
| 77 | |
| 78 | \ [ ] { } ^ ~ ! # | $ @ ` |
| 79 | |
| 80 | =head2 0037 |
| 81 | |
| 82 | Character code set ID 0037 is a mapping of the ASCII plus Latin-1 |
| 83 | characters (i.e. ISO 8859-1) to an EBCDIC set. 0037 is used |
| 84 | in North American English locales on the OS/400 operating system |
| 85 | that runs on AS/400 computers. CCSID 37 differs from ISO 8859-1 |
| 86 | in 237 places, in other words they agree on only 19 code point values. |
| 87 | |
| 88 | =head2 1047 |
| 89 | |
| 90 | Character code set ID 1047 is also a mapping of the ASCII plus |
| 91 | Latin-1 characters (i.e. ISO 8859-1) to an EBCDIC set. 1047 is |
| 92 | used under Unix System Services for OS/390 or z/OS, and OpenEdition |
| 93 | for VM/ESA. CCSID 1047 differs from CCSID 0037 in eight places. |
| 94 | |
| 95 | =head2 POSIX-BC |
| 96 | |
| 97 | The EBCDIC code page in use on Siemens' BS2000 system is distinct from |
| 98 | 1047 and 0037. It is identified below as the POSIX-BC set. |
| 99 | |
| 100 | =head2 Unicode code points versus EBCDIC code points |
| 101 | |
| 102 | In Unicode terminology a I<code point> is the number assigned to a |
| 103 | character: for example, in EBCDIC the character "A" is usually assigned |
| 104 | the number 193. In Unicode the character "A" is assigned the number 65. |
| 105 | This causes a problem with the semantics of the pack/unpack "U", which |
| 106 | are supposed to pack Unicode code points to characters and back to numbers. |
| 107 | The problem is: which code points to use for code points less than 256? |
| 108 | (for 256 and over there's no problem: Unicode code points are used) |
| 109 | In EBCDIC, for the low 256 the EBCDIC code points are used. This |
| 110 | means that the equivalences |
| 111 | |
| 112 | pack("U", ord($character)) eq $character |
| 113 | unpack("U", $character) == ord $character |
| 114 | |
| 115 | will hold. (If Unicode code points were applied consistently over |
| 116 | all the possible code points, pack("U",ord("A")) would in EBCDIC |
| 117 | equal I<A with acute> or chr(101), and unpack("U", "A") would equal |
| 118 | 65, or I<non-breaking space>, not 193, or ord "A".) |
| 119 | |
| 120 | =head2 Remaining Perl Unicode problems in EBCDIC |
| 121 | |
| 122 | =over 4 |
| 123 | |
| 124 | =item * |
| 125 | |
| 126 | Many of the remaining seem to be related to case-insensitive matching: |
| 127 | for example, C<< /[\x{131}]/ >> (LATIN SMALL LETTER DOTLESS I) does |
| 128 | not match "I" case-insensitively, as it should under Unicode. |
| 129 | (The match succeeds in ASCII-derived platforms.) |
| 130 | |
| 131 | =item * |
| 132 | |
| 133 | The extensions Unicode::Collate and Unicode::Normalized are not |
| 134 | supported under EBCDIC, likewise for the encoding pragma. |
| 135 | |
| 136 | =back |
| 137 | |
| 138 | =head2 Unicode and UTF |
| 139 | |
| 140 | UTF is a Unicode Transformation Format. UTF-8 is a Unicode conforming |
| 141 | representation of the Unicode standard that looks very much like ASCII. |
| 142 | UTF-EBCDIC is an attempt to represent Unicode characters in an EBCDIC |
| 143 | transparent manner. |
| 144 | |
| 145 | =head2 Using Encode |
| 146 | |
| 147 | Starting from Perl 5.8 you can use the standard new module Encode |
| 148 | to translate from EBCDIC to Latin-1 code points |
| 149 | |
| 150 | use Encode 'from_to'; |
| 151 | |
| 152 | my %ebcdic = ( 176 => 'cp37', 95 => 'cp1047', 106 => 'posix-bc' ); |
| 153 | |
| 154 | # $a is in EBCDIC code points |
| 155 | from_to($a, $ebcdic{ord '^'}, 'latin1'); |
| 156 | # $a is ISO 8859-1 code points |
| 157 | |
| 158 | and from Latin-1 code points to EBCDIC code points |
| 159 | |
| 160 | use Encode 'from_to'; |
| 161 | |
| 162 | my %ebcdic = ( 176 => 'cp37', 95 => 'cp1047', 106 => 'posix-bc' ); |
| 163 | |
| 164 | # $a is ISO 8859-1 code points |
| 165 | from_to($a, 'latin1', $ebcdic{ord '^'}); |
| 166 | # $a is in EBCDIC code points |
| 167 | |
| 168 | For doing I/O it is suggested that you use the autotranslating features |
| 169 | of PerlIO, see L<perluniintro>. |
| 170 | |
| 171 | Since version 5.8 Perl uses the new PerlIO I/O library. This enables |
| 172 | you to use different encodings per IO channel. For example you may use |
| 173 | |
| 174 | use Encode; |
| 175 | open($f, ">:encoding(ascii)", "test.ascii"); |
| 176 | print $f "Hello World!\n"; |
| 177 | open($f, ">:encoding(cp37)", "test.ebcdic"); |
| 178 | print $f "Hello World!\n"; |
| 179 | open($f, ">:encoding(latin1)", "test.latin1"); |
| 180 | print $f "Hello World!\n"; |
| 181 | open($f, ">:encoding(utf8)", "test.utf8"); |
| 182 | print $f "Hello World!\n"; |
| 183 | |
| 184 | to get two files containing "Hello World!\n" in ASCII, CP 37 EBCDIC, |
| 185 | ISO 8859-1 (Latin-1) (in this example identical to ASCII) respective |
| 186 | UTF-EBCDIC (in this example identical to normal EBCDIC). See the |
| 187 | documentation of Encode::PerlIO for details. |
| 188 | |
| 189 | As the PerlIO layer uses raw IO (bytes) internally, all this totally |
| 190 | ignores things like the type of your filesystem (ASCII or EBCDIC). |
| 191 | |
| 192 | =head1 SINGLE OCTET TABLES |
| 193 | |
| 194 | The following tables list the ASCII and Latin 1 ordered sets including |
| 195 | the subsets: C0 controls (0..31), ASCII graphics (32..7e), delete (7f), |
| 196 | C1 controls (80..9f), and Latin-1 (a.k.a. ISO 8859-1) (a0..ff). In the |
| 197 | table non-printing control character names as well as the Latin 1 |
| 198 | extensions to ASCII have been labelled with character names roughly |
| 199 | corresponding to I<The Unicode Standard, Version 3.0> albeit with |
| 200 | substitutions such as s/LATIN// and s/VULGAR// in all cases, |
| 201 | s/CAPITAL LETTER// in some cases, and s/SMALL LETTER ([A-Z])/\l$1/ |
| 202 | in some other cases (the C<charnames> pragma names unfortunately do |
| 203 | not list explicit names for the C0 or C1 control characters). The |
| 204 | "names" of the C1 control set (128..159 in ISO 8859-1) listed here are |
| 205 | somewhat arbitrary. The differences between the 0037 and 1047 sets are |
| 206 | flagged with ***. The differences between the 1047 and POSIX-BC sets |
| 207 | are flagged with ###. All ord() numbers listed are decimal. If you |
| 208 | would rather see this table listing octal values then run the table |
| 209 | (that is, the pod version of this document since this recipe may not |
| 210 | work with a pod2_other_format translation) through: |
| 211 | |
| 212 | =over 4 |
| 213 | |
| 214 | =item recipe 0 |
| 215 | |
| 216 | =back |
| 217 | |
| 218 | perl -ne 'if(/(.{33})(\d+)\s+(\d+)\s+(\d+)\s+(\d+)/)' \ |
| 219 | -e '{printf("%s%-9o%-9o%-9o%o\n",$1,$2,$3,$4,$5)}' perlebcdic.pod |
| 220 | |
| 221 | If you want to retain the UTF-x code points then in script form you |
| 222 | might want to write: |
| 223 | |
| 224 | =over 4 |
| 225 | |
| 226 | =item recipe 1 |
| 227 | |
| 228 | =back |
| 229 | |
| 230 | open(FH,"<perlebcdic.pod") or die "Could not open perlebcdic.pod: $!"; |
| 231 | while (<FH>) { |
| 232 | if (/(.{33})(\d+)\s+(\d+)\s+(\d+)\s+(\d+)\s+(\d+)\.?(\d*)\s+(\d+)\.?(\d*)/) { |
| 233 | if ($7 ne '' && $9 ne '') { |
| 234 | printf("%s%-9o%-9o%-9o%-9o%-3o.%-5o%-3o.%o\n",$1,$2,$3,$4,$5,$6,$7,$8,$9); |
| 235 | } |
| 236 | elsif ($7 ne '') { |
| 237 | printf("%s%-9o%-9o%-9o%-9o%-3o.%-5o%o\n",$1,$2,$3,$4,$5,$6,$7,$8); |
| 238 | } |
| 239 | else { |
| 240 | printf("%s%-9o%-9o%-9o%-9o%-9o%o\n",$1,$2,$3,$4,$5,$6,$8); |
| 241 | } |
| 242 | } |
| 243 | } |
| 244 | |
| 245 | If you would rather see this table listing hexadecimal values then |
| 246 | run the table through: |
| 247 | |
| 248 | =over 4 |
| 249 | |
| 250 | =item recipe 2 |
| 251 | |
| 252 | =back |
| 253 | |
| 254 | perl -ne 'if(/(.{33})(\d+)\s+(\d+)\s+(\d+)\s+(\d+)/)' \ |
| 255 | -e '{printf("%s%-9X%-9X%-9X%X\n",$1,$2,$3,$4,$5)}' perlebcdic.pod |
| 256 | |
| 257 | Or, in order to retain the UTF-x code points in hexadecimal: |
| 258 | |
| 259 | =over 4 |
| 260 | |
| 261 | =item recipe 3 |
| 262 | |
| 263 | =back |
| 264 | |
| 265 | open(FH,"<perlebcdic.pod") or die "Could not open perlebcdic.pod: $!"; |
| 266 | while (<FH>) { |
| 267 | if (/(.{33})(\d+)\s+(\d+)\s+(\d+)\s+(\d+)\s+(\d+)\.?(\d*)\s+(\d+)\.?(\d*)/) { |
| 268 | if ($7 ne '' && $9 ne '') { |
| 269 | printf("%s%-9X%-9X%-9X%-9X%-2X.%-6X%-2X.%X\n",$1,$2,$3,$4,$5,$6,$7,$8,$9); |
| 270 | } |
| 271 | elsif ($7 ne '') { |
| 272 | printf("%s%-9X%-9X%-9X%-9X%-2X.%-6X%X\n",$1,$2,$3,$4,$5,$6,$7,$8); |
| 273 | } |
| 274 | else { |
| 275 | printf("%s%-9X%-9X%-9X%-9X%-9X%X\n",$1,$2,$3,$4,$5,$6,$8); |
| 276 | } |
| 277 | } |
| 278 | } |
| 279 | |
| 280 | |
| 281 | incomp- incomp- |
| 282 | 8859-1 lete lete |
| 283 | chr 0819 0037 1047 POSIX-BC UTF-8 UTF-EBCDIC |
| 284 | ------------------------------------------------------------------------------------ |
| 285 | <NULL> 0 0 0 0 0 0 |
| 286 | <START OF HEADING> 1 1 1 1 1 1 |
| 287 | <START OF TEXT> 2 2 2 2 2 2 |
| 288 | <END OF TEXT> 3 3 3 3 3 3 |
| 289 | <END OF TRANSMISSION> 4 55 55 55 4 55 |
| 290 | <ENQUIRY> 5 45 45 45 5 45 |
| 291 | <ACKNOWLEDGE> 6 46 46 46 6 46 |
| 292 | <BELL> 7 47 47 47 7 47 |
| 293 | <BACKSPACE> 8 22 22 22 8 22 |
| 294 | <HORIZONTAL TABULATION> 9 5 5 5 9 5 |
| 295 | <LINE FEED> 10 37 21 21 10 21 *** |
| 296 | <VERTICAL TABULATION> 11 11 11 11 11 11 |
| 297 | <FORM FEED> 12 12 12 12 12 12 |
| 298 | <CARRIAGE RETURN> 13 13 13 13 13 13 |
| 299 | <SHIFT OUT> 14 14 14 14 14 14 |
| 300 | <SHIFT IN> 15 15 15 15 15 15 |
| 301 | <DATA LINK ESCAPE> 16 16 16 16 16 16 |
| 302 | <DEVICE CONTROL ONE> 17 17 17 17 17 17 |
| 303 | <DEVICE CONTROL TWO> 18 18 18 18 18 18 |
| 304 | <DEVICE CONTROL THREE> 19 19 19 19 19 19 |
| 305 | <DEVICE CONTROL FOUR> 20 60 60 60 20 60 |
| 306 | <NEGATIVE ACKNOWLEDGE> 21 61 61 61 21 61 |
| 307 | <SYNCHRONOUS IDLE> 22 50 50 50 22 50 |
| 308 | <END OF TRANSMISSION BLOCK> 23 38 38 38 23 38 |
| 309 | <CANCEL> 24 24 24 24 24 24 |
| 310 | <END OF MEDIUM> 25 25 25 25 25 25 |
| 311 | <SUBSTITUTE> 26 63 63 63 26 63 |
| 312 | <ESCAPE> 27 39 39 39 27 39 |
| 313 | <FILE SEPARATOR> 28 28 28 28 28 28 |
| 314 | <GROUP SEPARATOR> 29 29 29 29 29 29 |
| 315 | <RECORD SEPARATOR> 30 30 30 30 30 30 |
| 316 | <UNIT SEPARATOR> 31 31 31 31 31 31 |
| 317 | <SPACE> 32 64 64 64 32 64 |
| 318 | ! 33 90 90 90 33 90 |
| 319 | " 34 127 127 127 34 127 |
| 320 | # 35 123 123 123 35 123 |
| 321 | $ 36 91 91 91 36 91 |
| 322 | % 37 108 108 108 37 108 |
| 323 | & 38 80 80 80 38 80 |
| 324 | ' 39 125 125 125 39 125 |
| 325 | ( 40 77 77 77 40 77 |
| 326 | ) 41 93 93 93 41 93 |
| 327 | * 42 92 92 92 42 92 |
| 328 | + 43 78 78 78 43 78 |
| 329 | , 44 107 107 107 44 107 |
| 330 | - 45 96 96 96 45 96 |
| 331 | . 46 75 75 75 46 75 |
| 332 | / 47 97 97 97 47 97 |
| 333 | 0 48 240 240 240 48 240 |
| 334 | 1 49 241 241 241 49 241 |
| 335 | 2 50 242 242 242 50 242 |
| 336 | 3 51 243 243 243 51 243 |
| 337 | 4 52 244 244 244 52 244 |
| 338 | 5 53 245 245 245 53 245 |
| 339 | 6 54 246 246 246 54 246 |
| 340 | 7 55 247 247 247 55 247 |
| 341 | 8 56 248 248 248 56 248 |
| 342 | 9 57 249 249 249 57 249 |
| 343 | : 58 122 122 122 58 122 |
| 344 | ; 59 94 94 94 59 94 |
| 345 | < 60 76 76 76 60 76 |
| 346 | = 61 126 126 126 61 126 |
| 347 | > 62 110 110 110 62 110 |
| 348 | ? 63 111 111 111 63 111 |
| 349 | @ 64 124 124 124 64 124 |
| 350 | A 65 193 193 193 65 193 |
| 351 | B 66 194 194 194 66 194 |
| 352 | C 67 195 195 195 67 195 |
| 353 | D 68 196 196 196 68 196 |
| 354 | E 69 197 197 197 69 197 |
| 355 | F 70 198 198 198 70 198 |
| 356 | G 71 199 199 199 71 199 |
| 357 | H 72 200 200 200 72 200 |
| 358 | I 73 201 201 201 73 201 |
| 359 | J 74 209 209 209 74 209 |
| 360 | K 75 210 210 210 75 210 |
| 361 | L 76 211 211 211 76 211 |
| 362 | M 77 212 212 212 77 212 |
| 363 | N 78 213 213 213 78 213 |
| 364 | O 79 214 214 214 79 214 |
| 365 | P 80 215 215 215 80 215 |
| 366 | Q 81 216 216 216 81 216 |
| 367 | R 82 217 217 217 82 217 |
| 368 | S 83 226 226 226 83 226 |
| 369 | T 84 227 227 227 84 227 |
| 370 | U 85 228 228 228 85 228 |
| 371 | V 86 229 229 229 86 229 |
| 372 | W 87 230 230 230 87 230 |
| 373 | X 88 231 231 231 88 231 |
| 374 | Y 89 232 232 232 89 232 |
| 375 | Z 90 233 233 233 90 233 |
| 376 | [ 91 186 173 187 91 173 *** ### |
| 377 | \ 92 224 224 188 92 224 ### |
| 378 | ] 93 187 189 189 93 189 *** |
| 379 | ^ 94 176 95 106 94 95 *** ### |
| 380 | _ 95 109 109 109 95 109 |
| 381 | ` 96 121 121 74 96 121 ### |
| 382 | a 97 129 129 129 97 129 |
| 383 | b 98 130 130 130 98 130 |
| 384 | c 99 131 131 131 99 131 |
| 385 | d 100 132 132 132 100 132 |
| 386 | e 101 133 133 133 101 133 |
| 387 | f 102 134 134 134 102 134 |
| 388 | g 103 135 135 135 103 135 |
| 389 | h 104 136 136 136 104 136 |
| 390 | i 105 137 137 137 105 137 |
| 391 | j 106 145 145 145 106 145 |
| 392 | k 107 146 146 146 107 146 |
| 393 | l 108 147 147 147 108 147 |
| 394 | m 109 148 148 148 109 148 |
| 395 | n 110 149 149 149 110 149 |
| 396 | o 111 150 150 150 111 150 |
| 397 | p 112 151 151 151 112 151 |
| 398 | q 113 152 152 152 113 152 |
| 399 | r 114 153 153 153 114 153 |
| 400 | s 115 162 162 162 115 162 |
| 401 | t 116 163 163 163 116 163 |
| 402 | u 117 164 164 164 117 164 |
| 403 | v 118 165 165 165 118 165 |
| 404 | w 119 166 166 166 119 166 |
| 405 | x 120 167 167 167 120 167 |
| 406 | y 121 168 168 168 121 168 |
| 407 | z 122 169 169 169 122 169 |
| 408 | { 123 192 192 251 123 192 ### |
| 409 | | 124 79 79 79 124 79 |
| 410 | } 125 208 208 253 125 208 ### |
| 411 | ~ 126 161 161 255 126 161 ### |
| 412 | <DELETE> 127 7 7 7 127 7 |
| 413 | <C1 0> 128 32 32 32 194.128 32 |
| 414 | <C1 1> 129 33 33 33 194.129 33 |
| 415 | <C1 2> 130 34 34 34 194.130 34 |
| 416 | <C1 3> 131 35 35 35 194.131 35 |
| 417 | <C1 4> 132 36 36 36 194.132 36 |
| 418 | <C1 5> 133 21 37 37 194.133 37 *** |
| 419 | <C1 6> 134 6 6 6 194.134 6 |
| 420 | <C1 7> 135 23 23 23 194.135 23 |
| 421 | <C1 8> 136 40 40 40 194.136 40 |
| 422 | <C1 9> 137 41 41 41 194.137 41 |
| 423 | <C1 10> 138 42 42 42 194.138 42 |
| 424 | <C1 11> 139 43 43 43 194.139 43 |
| 425 | <C1 12> 140 44 44 44 194.140 44 |
| 426 | <C1 13> 141 9 9 9 194.141 9 |
| 427 | <C1 14> 142 10 10 10 194.142 10 |
| 428 | <C1 15> 143 27 27 27 194.143 27 |
| 429 | <C1 16> 144 48 48 48 194.144 48 |
| 430 | <C1 17> 145 49 49 49 194.145 49 |
| 431 | <C1 18> 146 26 26 26 194.146 26 |
| 432 | <C1 19> 147 51 51 51 194.147 51 |
| 433 | <C1 20> 148 52 52 52 194.148 52 |
| 434 | <C1 21> 149 53 53 53 194.149 53 |
| 435 | <C1 22> 150 54 54 54 194.150 54 |
| 436 | <C1 23> 151 8 8 8 194.151 8 |
| 437 | <C1 24> 152 56 56 56 194.152 56 |
| 438 | <C1 25> 153 57 57 57 194.153 57 |
| 439 | <C1 26> 154 58 58 58 194.154 58 |
| 440 | <C1 27> 155 59 59 59 194.155 59 |
| 441 | <C1 28> 156 4 4 4 194.156 4 |
| 442 | <C1 29> 157 20 20 20 194.157 20 |
| 443 | <C1 30> 158 62 62 62 194.158 62 |
| 444 | <C1 31> 159 255 255 95 194.159 255 ### |
| 445 | <NON-BREAKING SPACE> 160 65 65 65 194.160 128.65 |
| 446 | <INVERTED EXCLAMATION MARK> 161 170 170 170 194.161 128.66 |
| 447 | <CENT SIGN> 162 74 74 176 194.162 128.67 ### |
| 448 | <POUND SIGN> 163 177 177 177 194.163 128.68 |
| 449 | <CURRENCY SIGN> 164 159 159 159 194.164 128.69 |
| 450 | <YEN SIGN> 165 178 178 178 194.165 128.70 |
| 451 | <BROKEN BAR> 166 106 106 208 194.166 128.71 ### |
| 452 | <SECTION SIGN> 167 181 181 181 194.167 128.72 |
| 453 | <DIAERESIS> 168 189 187 121 194.168 128.73 *** ### |
| 454 | <COPYRIGHT SIGN> 169 180 180 180 194.169 128.74 |
| 455 | <FEMININE ORDINAL INDICATOR> 170 154 154 154 194.170 128.81 |
| 456 | <LEFT POINTING GUILLEMET> 171 138 138 138 194.171 128.82 |
| 457 | <NOT SIGN> 172 95 176 186 194.172 128.83 *** ### |
| 458 | <SOFT HYPHEN> 173 202 202 202 194.173 128.84 |
| 459 | <REGISTERED TRADE MARK SIGN> 174 175 175 175 194.174 128.85 |
| 460 | <MACRON> 175 188 188 161 194.175 128.86 ### |
| 461 | <DEGREE SIGN> 176 144 144 144 194.176 128.87 |
| 462 | <PLUS-OR-MINUS SIGN> 177 143 143 143 194.177 128.88 |
| 463 | <SUPERSCRIPT TWO> 178 234 234 234 194.178 128.89 |
| 464 | <SUPERSCRIPT THREE> 179 250 250 250 194.179 128.98 |
| 465 | <ACUTE ACCENT> 180 190 190 190 194.180 128.99 |
| 466 | <MICRO SIGN> 181 160 160 160 194.181 128.100 |
| 467 | <PARAGRAPH SIGN> 182 182 182 182 194.182 128.101 |
| 468 | <MIDDLE DOT> 183 179 179 179 194.183 128.102 |
| 469 | <CEDILLA> 184 157 157 157 194.184 128.103 |
| 470 | <SUPERSCRIPT ONE> 185 218 218 218 194.185 128.104 |
| 471 | <MASC. ORDINAL INDICATOR> 186 155 155 155 194.186 128.105 |
| 472 | <RIGHT POINTING GUILLEMET> 187 139 139 139 194.187 128.106 |
| 473 | <FRACTION ONE QUARTER> 188 183 183 183 194.188 128.112 |
| 474 | <FRACTION ONE HALF> 189 184 184 184 194.189 128.113 |
| 475 | <FRACTION THREE QUARTERS> 190 185 185 185 194.190 128.114 |
| 476 | <INVERTED QUESTION MARK> 191 171 171 171 194.191 128.115 |
| 477 | <A WITH GRAVE> 192 100 100 100 195.128 138.65 |
| 478 | <A WITH ACUTE> 193 101 101 101 195.129 138.66 |
| 479 | <A WITH CIRCUMFLEX> 194 98 98 98 195.130 138.67 |
| 480 | <A WITH TILDE> 195 102 102 102 195.131 138.68 |
| 481 | <A WITH DIAERESIS> 196 99 99 99 195.132 138.69 |
| 482 | <A WITH RING ABOVE> 197 103 103 103 195.133 138.70 |
| 483 | <CAPITAL LIGATURE AE> 198 158 158 158 195.134 138.71 |
| 484 | <C WITH CEDILLA> 199 104 104 104 195.135 138.72 |
| 485 | <E WITH GRAVE> 200 116 116 116 195.136 138.73 |
| 486 | <E WITH ACUTE> 201 113 113 113 195.137 138.74 |
| 487 | <E WITH CIRCUMFLEX> 202 114 114 114 195.138 138.81 |
| 488 | <E WITH DIAERESIS> 203 115 115 115 195.139 138.82 |
| 489 | <I WITH GRAVE> 204 120 120 120 195.140 138.83 |
| 490 | <I WITH ACUTE> 205 117 117 117 195.141 138.84 |
| 491 | <I WITH CIRCUMFLEX> 206 118 118 118 195.142 138.85 |
| 492 | <I WITH DIAERESIS> 207 119 119 119 195.143 138.86 |
| 493 | <CAPITAL LETTER ETH> 208 172 172 172 195.144 138.87 |
| 494 | <N WITH TILDE> 209 105 105 105 195.145 138.88 |
| 495 | <O WITH GRAVE> 210 237 237 237 195.146 138.89 |
| 496 | <O WITH ACUTE> 211 238 238 238 195.147 138.98 |
| 497 | <O WITH CIRCUMFLEX> 212 235 235 235 195.148 138.99 |
| 498 | <O WITH TILDE> 213 239 239 239 195.149 138.100 |
| 499 | <O WITH DIAERESIS> 214 236 236 236 195.150 138.101 |
| 500 | <MULTIPLICATION SIGN> 215 191 191 191 195.151 138.102 |
| 501 | <O WITH STROKE> 216 128 128 128 195.152 138.103 |
| 502 | <U WITH GRAVE> 217 253 253 224 195.153 138.104 ### |
| 503 | <U WITH ACUTE> 218 254 254 254 195.154 138.105 |
| 504 | <U WITH CIRCUMFLEX> 219 251 251 221 195.155 138.106 ### |
| 505 | <U WITH DIAERESIS> 220 252 252 252 195.156 138.112 |
| 506 | <Y WITH ACUTE> 221 173 186 173 195.157 138.113 *** ### |
| 507 | <CAPITAL LETTER THORN> 222 174 174 174 195.158 138.114 |
| 508 | <SMALL LETTER SHARP S> 223 89 89 89 195.159 138.115 |
| 509 | <a WITH GRAVE> 224 68 68 68 195.160 139.65 |
| 510 | <a WITH ACUTE> 225 69 69 69 195.161 139.66 |
| 511 | <a WITH CIRCUMFLEX> 226 66 66 66 195.162 139.67 |
| 512 | <a WITH TILDE> 227 70 70 70 195.163 139.68 |
| 513 | <a WITH DIAERESIS> 228 67 67 67 195.164 139.69 |
| 514 | <a WITH RING ABOVE> 229 71 71 71 195.165 139.70 |
| 515 | <SMALL LIGATURE ae> 230 156 156 156 195.166 139.71 |
| 516 | <c WITH CEDILLA> 231 72 72 72 195.167 139.72 |
| 517 | <e WITH GRAVE> 232 84 84 84 195.168 139.73 |
| 518 | <e WITH ACUTE> 233 81 81 81 195.169 139.74 |
| 519 | <e WITH CIRCUMFLEX> 234 82 82 82 195.170 139.81 |
| 520 | <e WITH DIAERESIS> 235 83 83 83 195.171 139.82 |
| 521 | <i WITH GRAVE> 236 88 88 88 195.172 139.83 |
| 522 | <i WITH ACUTE> 237 85 85 85 195.173 139.84 |
| 523 | <i WITH CIRCUMFLEX> 238 86 86 86 195.174 139.85 |
| 524 | <i WITH DIAERESIS> 239 87 87 87 195.175 139.86 |
| 525 | <SMALL LETTER eth> 240 140 140 140 195.176 139.87 |
| 526 | <n WITH TILDE> 241 73 73 73 195.177 139.88 |
| 527 | <o WITH GRAVE> 242 205 205 205 195.178 139.89 |
| 528 | <o WITH ACUTE> 243 206 206 206 195.179 139.98 |
| 529 | <o WITH CIRCUMFLEX> 244 203 203 203 195.180 139.99 |
| 530 | <o WITH TILDE> 245 207 207 207 195.181 139.100 |
| 531 | <o WITH DIAERESIS> 246 204 204 204 195.182 139.101 |
| 532 | <DIVISION SIGN> 247 225 225 225 195.183 139.102 |
| 533 | <o WITH STROKE> 248 112 112 112 195.184 139.103 |
| 534 | <u WITH GRAVE> 249 221 221 192 195.185 139.104 ### |
| 535 | <u WITH ACUTE> 250 222 222 222 195.186 139.105 |
| 536 | <u WITH CIRCUMFLEX> 251 219 219 219 195.187 139.106 |
| 537 | <u WITH DIAERESIS> 252 220 220 220 195.188 139.112 |
| 538 | <y WITH ACUTE> 253 141 141 141 195.189 139.113 |
| 539 | <SMALL LETTER thorn> 254 142 142 142 195.190 139.114 |
| 540 | <y WITH DIAERESIS> 255 223 223 223 195.191 139.115 |
| 541 | |
| 542 | If you would rather see the above table in CCSID 0037 order rather than |
| 543 | ASCII + Latin-1 order then run the table through: |
| 544 | |
| 545 | =over 4 |
| 546 | |
| 547 | =item recipe 4 |
| 548 | |
| 549 | =back |
| 550 | |
| 551 | 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}/)'\ |
| 552 | -e '{push(@l,$_)}' \ |
| 553 | -e 'END{print map{$_->[0]}' \ |
| 554 | -e ' sort{$a->[1] <=> $b->[1]}' \ |
| 555 | -e ' map{[$_,substr($_,42,3)]}@l;}' perlebcdic.pod |
| 556 | |
| 557 | If you would rather see it in CCSID 1047 order then change the digit |
| 558 | 42 in the last line to 51, like this: |
| 559 | |
| 560 | =over 4 |
| 561 | |
| 562 | =item recipe 5 |
| 563 | |
| 564 | =back |
| 565 | |
| 566 | perl -ne 'if(/.{33}\d{1,3}\s{6,8}\d{1,3}\s{6,8}\d{1,3}\s{6,8}\d{1,3}/)'\ |
| 567 | -e '{push(@l,$_)}' \ |
| 568 | -e 'END{print map{$_->[0]}' \ |
| 569 | -e ' sort{$a->[1] <=> $b->[1]}' \ |
| 570 | -e ' map{[$_,substr($_,51,3)]}@l;}' perlebcdic.pod |
| 571 | |
| 572 | If you would rather see it in POSIX-BC order then change the digit |
| 573 | 51 in the last line to 60, like this: |
| 574 | |
| 575 | =over 4 |
| 576 | |
| 577 | =item recipe 6 |
| 578 | |
| 579 | =back |
| 580 | |
| 581 | perl -ne 'if(/.{33}\d{1,3}\s{6,8}\d{1,3}\s{6,8}\d{1,3}\s{6,8}\d{1,3}/)'\ |
| 582 | -e '{push(@l,$_)}' \ |
| 583 | -e 'END{print map{$_->[0]}' \ |
| 584 | -e ' sort{$a->[1] <=> $b->[1]}' \ |
| 585 | -e ' map{[$_,substr($_,60,3)]}@l;}' perlebcdic.pod |
| 586 | |
| 587 | |
| 588 | =head1 IDENTIFYING CHARACTER CODE SETS |
| 589 | |
| 590 | To determine the character set you are running under from perl one |
| 591 | could use the return value of ord() or chr() to test one or more |
| 592 | character values. For example: |
| 593 | |
| 594 | $is_ascii = "A" eq chr(65); |
| 595 | $is_ebcdic = "A" eq chr(193); |
| 596 | |
| 597 | Also, "\t" is a C<HORIZONTAL TABULATION> character so that: |
| 598 | |
| 599 | $is_ascii = ord("\t") == 9; |
| 600 | $is_ebcdic = ord("\t") == 5; |
| 601 | |
| 602 | To distinguish EBCDIC code pages try looking at one or more of |
| 603 | the characters that differ between them. For example: |
| 604 | |
| 605 | $is_ebcdic_37 = "\n" eq chr(37); |
| 606 | $is_ebcdic_1047 = "\n" eq chr(21); |
| 607 | |
| 608 | Or better still choose a character that is uniquely encoded in any |
| 609 | of the code sets, e.g.: |
| 610 | |
| 611 | $is_ascii = ord('[') == 91; |
| 612 | $is_ebcdic_37 = ord('[') == 186; |
| 613 | $is_ebcdic_1047 = ord('[') == 173; |
| 614 | $is_ebcdic_POSIX_BC = ord('[') == 187; |
| 615 | |
| 616 | However, it would be unwise to write tests such as: |
| 617 | |
| 618 | $is_ascii = "\r" ne chr(13); # WRONG |
| 619 | $is_ascii = "\n" ne chr(10); # ILL ADVISED |
| 620 | |
| 621 | Obviously the first of these will fail to distinguish most ASCII machines |
| 622 | from either a CCSID 0037, a 1047, or a POSIX-BC EBCDIC machine since "\r" eq |
| 623 | chr(13) under all of those coded character sets. But note too that |
| 624 | because "\n" is chr(13) and "\r" is chr(10) on the MacIntosh (which is an |
| 625 | ASCII machine) the second C<$is_ascii> test will lead to trouble there. |
| 626 | |
| 627 | To determine whether or not perl was built under an EBCDIC |
| 628 | code page you can use the Config module like so: |
| 629 | |
| 630 | use Config; |
| 631 | $is_ebcdic = $Config{'ebcdic'} eq 'define'; |
| 632 | |
| 633 | =head1 CONVERSIONS |
| 634 | |
| 635 | =head2 tr/// |
| 636 | |
| 637 | In order to convert a string of characters from one character set to |
| 638 | another a simple list of numbers, such as in the right columns in the |
| 639 | above table, along with perl's tr/// operator is all that is needed. |
| 640 | The data in the table are in ASCII order hence the EBCDIC columns |
| 641 | provide easy to use ASCII to EBCDIC operations that are also easily |
| 642 | reversed. |
| 643 | |
| 644 | For example, to convert ASCII to code page 037 take the output of the second |
| 645 | column from the output of recipe 0 (modified to add \\ characters) and use |
| 646 | it in tr/// like so: |
| 647 | |
| 648 | $cp_037 = |
| 649 | '\000\001\002\003\234\011\206\177\227\215\216\013\014\015\016\017' . |
| 650 | '\020\021\022\023\235\205\010\207\030\031\222\217\034\035\036\037' . |
| 651 | '\200\201\202\203\204\012\027\033\210\211\212\213\214\005\006\007' . |
| 652 | '\220\221\026\223\224\225\226\004\230\231\232\233\024\025\236\032' . |
| 653 | '\040\240\342\344\340\341\343\345\347\361\242\056\074\050\053\174' . |
| 654 | '\046\351\352\353\350\355\356\357\354\337\041\044\052\051\073\254' . |
| 655 | '\055\057\302\304\300\301\303\305\307\321\246\054\045\137\076\077' . |
| 656 | '\370\311\312\313\310\315\316\317\314\140\072\043\100\047\075\042' . |
| 657 | '\330\141\142\143\144\145\146\147\150\151\253\273\360\375\376\261' . |
| 658 | '\260\152\153\154\155\156\157\160\161\162\252\272\346\270\306\244' . |
| 659 | '\265\176\163\164\165\166\167\170\171\172\241\277\320\335\336\256' . |
| 660 | '\136\243\245\267\251\247\266\274\275\276\133\135\257\250\264\327' . |
| 661 | '\173\101\102\103\104\105\106\107\110\111\255\364\366\362\363\365' . |
| 662 | '\175\112\113\114\115\116\117\120\121\122\271\373\374\371\372\377' . |
| 663 | '\134\367\123\124\125\126\127\130\131\132\262\324\326\322\323\325' . |
| 664 | '\060\061\062\063\064\065\066\067\070\071\263\333\334\331\332\237' ; |
| 665 | |
| 666 | my $ebcdic_string = $ascii_string; |
| 667 | eval '$ebcdic_string =~ tr/' . $cp_037 . '/\000-\377/'; |
| 668 | |
| 669 | To convert from EBCDIC 037 to ASCII just reverse the order of the tr/// |
| 670 | arguments like so: |
| 671 | |
| 672 | my $ascii_string = $ebcdic_string; |
| 673 | eval '$ascii_string =~ tr/\000-\377/' . $cp_037 . '/'; |
| 674 | |
| 675 | Similarly one could take the output of the third column from recipe 0 to |
| 676 | obtain a C<$cp_1047> table. The fourth column of the output from recipe |
| 677 | 0 could provide a C<$cp_posix_bc> table suitable for transcoding as well. |
| 678 | |
| 679 | =head2 iconv |
| 680 | |
| 681 | XPG operability often implies the presence of an I<iconv> utility |
| 682 | available from the shell or from the C library. Consult your system's |
| 683 | documentation for information on iconv. |
| 684 | |
| 685 | On OS/390 or z/OS see the iconv(1) manpage. One way to invoke the iconv |
| 686 | shell utility from within perl would be to: |
| 687 | |
| 688 | # OS/390 or z/OS example |
| 689 | $ascii_data = `echo '$ebcdic_data'| iconv -f IBM-1047 -t ISO8859-1` |
| 690 | |
| 691 | or the inverse map: |
| 692 | |
| 693 | # OS/390 or z/OS example |
| 694 | $ebcdic_data = `echo '$ascii_data'| iconv -f ISO8859-1 -t IBM-1047` |
| 695 | |
| 696 | For other perl based conversion options see the Convert::* modules on CPAN. |
| 697 | |
| 698 | =head2 C RTL |
| 699 | |
| 700 | The OS/390 and z/OS C run time libraries provide _atoe() and _etoa() functions. |
| 701 | |
| 702 | =head1 OPERATOR DIFFERENCES |
| 703 | |
| 704 | The C<..> range operator treats certain character ranges with |
| 705 | care on EBCDIC machines. For example the following array |
| 706 | will have twenty six elements on either an EBCDIC machine |
| 707 | or an ASCII machine: |
| 708 | |
| 709 | @alphabet = ('A'..'Z'); # $#alphabet == 25 |
| 710 | |
| 711 | The bitwise operators such as & ^ | may return different results |
| 712 | when operating on string or character data in a perl program running |
| 713 | on an EBCDIC machine than when run on an ASCII machine. Here is |
| 714 | an example adapted from the one in L<perlop>: |
| 715 | |
| 716 | # EBCDIC-based examples |
| 717 | print "j p \n" ^ " a h"; # prints "JAPH\n" |
| 718 | print "JA" | " ph\n"; # prints "japh\n" |
| 719 | print "JAPH\nJunk" & "\277\277\277\277\277"; # prints "japh\n"; |
| 720 | print 'p N$' ^ " E<H\n"; # prints "Perl\n"; |
| 721 | |
| 722 | An interesting property of the 32 C0 control characters |
| 723 | in the ASCII table is that they can "literally" be constructed |
| 724 | as control characters in perl, e.g. C<(chr(0) eq "\c@")> |
| 725 | C<(chr(1) eq "\cA")>, and so on. Perl on EBCDIC machines has been |
| 726 | ported to take "\c@" to chr(0) and "\cA" to chr(1) as well, but the |
| 727 | thirty three characters that result depend on which code page you are |
| 728 | using. The table below uses the character names from the previous table |
| 729 | but with substitutions such as s/START OF/S.O./; s/END OF /E.O./; |
| 730 | s/TRANSMISSION/TRANS./; s/TABULATION/TAB./; s/VERTICAL/VERT./; |
| 731 | s/HORIZONTAL/HORIZ./; s/DEVICE CONTROL/D.C./; s/SEPARATOR/SEP./; |
| 732 | s/NEGATIVE ACKNOWLEDGE/NEG. ACK./;. The POSIX-BC and 1047 sets are |
| 733 | identical throughout this range and differ from the 0037 set at only |
| 734 | one spot (21 decimal). Note that the C<LINE FEED> character |
| 735 | may be generated by "\cJ" on ASCII machines but by "\cU" on 1047 or POSIX-BC |
| 736 | machines and cannot be generated as a C<"\c.letter."> control character on |
| 737 | 0037 machines. Note also that "\c\\" maps to two characters |
| 738 | not one. |
| 739 | |
| 740 | chr ord 8859-1 0037 1047 && POSIX-BC |
| 741 | ------------------------------------------------------------------------ |
| 742 | "\c?" 127 <DELETE> " " ***>< |
| 743 | "\c@" 0 <NULL> <NULL> <NULL> ***>< |
| 744 | "\cA" 1 <S.O. HEADING> <S.O. HEADING> <S.O. HEADING> |
| 745 | "\cB" 2 <S.O. TEXT> <S.O. TEXT> <S.O. TEXT> |
| 746 | "\cC" 3 <E.O. TEXT> <E.O. TEXT> <E.O. TEXT> |
| 747 | "\cD" 4 <E.O. TRANS.> <C1 28> <C1 28> |
| 748 | "\cE" 5 <ENQUIRY> <HORIZ. TAB.> <HORIZ. TAB.> |
| 749 | "\cF" 6 <ACKNOWLEDGE> <C1 6> <C1 6> |
| 750 | "\cG" 7 <BELL> <DELETE> <DELETE> |
| 751 | "\cH" 8 <BACKSPACE> <C1 23> <C1 23> |
| 752 | "\cI" 9 <HORIZ. TAB.> <C1 13> <C1 13> |
| 753 | "\cJ" 10 <LINE FEED> <C1 14> <C1 14> |
| 754 | "\cK" 11 <VERT. TAB.> <VERT. TAB.> <VERT. TAB.> |
| 755 | "\cL" 12 <FORM FEED> <FORM FEED> <FORM FEED> |
| 756 | "\cM" 13 <CARRIAGE RETURN> <CARRIAGE RETURN> <CARRIAGE RETURN> |
| 757 | "\cN" 14 <SHIFT OUT> <SHIFT OUT> <SHIFT OUT> |
| 758 | "\cO" 15 <SHIFT IN> <SHIFT IN> <SHIFT IN> |
| 759 | "\cP" 16 <DATA LINK ESCAPE> <DATA LINK ESCAPE> <DATA LINK ESCAPE> |
| 760 | "\cQ" 17 <D.C. ONE> <D.C. ONE> <D.C. ONE> |
| 761 | "\cR" 18 <D.C. TWO> <D.C. TWO> <D.C. TWO> |
| 762 | "\cS" 19 <D.C. THREE> <D.C. THREE> <D.C. THREE> |
| 763 | "\cT" 20 <D.C. FOUR> <C1 29> <C1 29> |
| 764 | "\cU" 21 <NEG. ACK.> <C1 5> <LINE FEED> *** |
| 765 | "\cV" 22 <SYNCHRONOUS IDLE> <BACKSPACE> <BACKSPACE> |
| 766 | "\cW" 23 <E.O. TRANS. BLOCK> <C1 7> <C1 7> |
| 767 | "\cX" 24 <CANCEL> <CANCEL> <CANCEL> |
| 768 | "\cY" 25 <E.O. MEDIUM> <E.O. MEDIUM> <E.O. MEDIUM> |
| 769 | "\cZ" 26 <SUBSTITUTE> <C1 18> <C1 18> |
| 770 | "\c[" 27 <ESCAPE> <C1 15> <C1 15> |
| 771 | "\c\\" 28 <FILE SEP.>\ <FILE SEP.>\ <FILE SEP.>\ |
| 772 | "\c]" 29 <GROUP SEP.> <GROUP SEP.> <GROUP SEP.> |
| 773 | "\c^" 30 <RECORD SEP.> <RECORD SEP.> <RECORD SEP.> ***>< |
| 774 | "\c_" 31 <UNIT SEP.> <UNIT SEP.> <UNIT SEP.> ***>< |
| 775 | |
| 776 | |
| 777 | =head1 FUNCTION DIFFERENCES |
| 778 | |
| 779 | =over 8 |
| 780 | |
| 781 | =item chr() |
| 782 | |
| 783 | chr() must be given an EBCDIC code number argument to yield a desired |
| 784 | character return value on an EBCDIC machine. For example: |
| 785 | |
| 786 | $CAPITAL_LETTER_A = chr(193); |
| 787 | |
| 788 | =item ord() |
| 789 | |
| 790 | ord() will return EBCDIC code number values on an EBCDIC machine. |
| 791 | For example: |
| 792 | |
| 793 | $the_number_193 = ord("A"); |
| 794 | |
| 795 | =item pack() |
| 796 | |
| 797 | The c and C templates for pack() are dependent upon character set |
| 798 | encoding. Examples of usage on EBCDIC include: |
| 799 | |
| 800 | $foo = pack("CCCC",193,194,195,196); |
| 801 | # $foo eq "ABCD" |
| 802 | $foo = pack("C4",193,194,195,196); |
| 803 | # same thing |
| 804 | |
| 805 | $foo = pack("ccxxcc",193,194,195,196); |
| 806 | # $foo eq "AB\0\0CD" |
| 807 | |
| 808 | =item print() |
| 809 | |
| 810 | One must be careful with scalars and strings that are passed to |
| 811 | print that contain ASCII encodings. One common place |
| 812 | for this to occur is in the output of the MIME type header for |
| 813 | CGI script writing. For example, many perl programming guides |
| 814 | recommend something similar to: |
| 815 | |
| 816 | print "Content-type:\ttext/html\015\012\015\012"; |
| 817 | # this may be wrong on EBCDIC |
| 818 | |
| 819 | Under the IBM OS/390 USS Web Server or WebSphere on z/OS for example |
| 820 | you should instead write that as: |
| 821 | |
| 822 | print "Content-type:\ttext/html\r\n\r\n"; # OK for DGW et alia |
| 823 | |
| 824 | That is because the translation from EBCDIC to ASCII is done |
| 825 | by the web server in this case (such code will not be appropriate for |
| 826 | the Macintosh however). Consult your web server's documentation for |
| 827 | further details. |
| 828 | |
| 829 | =item printf() |
| 830 | |
| 831 | The formats that can convert characters to numbers and vice versa |
| 832 | will be different from their ASCII counterparts when executed |
| 833 | on an EBCDIC machine. Examples include: |
| 834 | |
| 835 | printf("%c%c%c",193,194,195); # prints ABC |
| 836 | |
| 837 | =item sort() |
| 838 | |
| 839 | EBCDIC sort results may differ from ASCII sort results especially for |
| 840 | mixed case strings. This is discussed in more detail below. |
| 841 | |
| 842 | =item sprintf() |
| 843 | |
| 844 | See the discussion of printf() above. An example of the use |
| 845 | of sprintf would be: |
| 846 | |
| 847 | $CAPITAL_LETTER_A = sprintf("%c",193); |
| 848 | |
| 849 | =item unpack() |
| 850 | |
| 851 | See the discussion of pack() above. |
| 852 | |
| 853 | =back |
| 854 | |
| 855 | =head1 REGULAR EXPRESSION DIFFERENCES |
| 856 | |
| 857 | As of perl 5.005_03 the letter range regular expression such as |
| 858 | [A-Z] and [a-z] have been especially coded to not pick up gap |
| 859 | characters. For example, characters such as E<ocirc> C<o WITH CIRCUMFLEX> |
| 860 | that lie between I and J would not be matched by the |
| 861 | regular expression range C</[H-K]/>. This works in |
| 862 | the other direction, too, if either of the range end points is |
| 863 | explicitly numeric: C<[\x89-\x91]> will match C<\x8e>, even |
| 864 | though C<\x89> is C<i> and C<\x91 > is C<j>, and C<\x8e> |
| 865 | is a gap character from the alphabetic viewpoint. |
| 866 | |
| 867 | If you do want to match the alphabet gap characters in a single octet |
| 868 | regular expression try matching the hex or octal code such |
| 869 | as C</\313/> on EBCDIC or C</\364/> on ASCII machines to |
| 870 | have your regular expression match C<o WITH CIRCUMFLEX>. |
| 871 | |
| 872 | Another construct to be wary of is the inappropriate use of hex or |
| 873 | octal constants in regular expressions. Consider the following |
| 874 | set of subs: |
| 875 | |
| 876 | sub is_c0 { |
| 877 | my $char = substr(shift,0,1); |
| 878 | $char =~ /[\000-\037]/; |
| 879 | } |
| 880 | |
| 881 | sub is_print_ascii { |
| 882 | my $char = substr(shift,0,1); |
| 883 | $char =~ /[\040-\176]/; |
| 884 | } |
| 885 | |
| 886 | sub is_delete { |
| 887 | my $char = substr(shift,0,1); |
| 888 | $char eq "\177"; |
| 889 | } |
| 890 | |
| 891 | sub is_c1 { |
| 892 | my $char = substr(shift,0,1); |
| 893 | $char =~ /[\200-\237]/; |
| 894 | } |
| 895 | |
| 896 | sub is_latin_1 { |
| 897 | my $char = substr(shift,0,1); |
| 898 | $char =~ /[\240-\377]/; |
| 899 | } |
| 900 | |
| 901 | The above would be adequate if the concern was only with numeric code points. |
| 902 | However, the concern may be with characters rather than code points |
| 903 | and on an EBCDIC machine it may be desirable for constructs such as |
| 904 | C<if (is_print_ascii("A")) {print "A is a printable character\n";}> to print |
| 905 | out the expected message. One way to represent the above collection |
| 906 | of character classification subs that is capable of working across the |
| 907 | four coded character sets discussed in this document is as follows: |
| 908 | |
| 909 | sub Is_c0 { |
| 910 | my $char = substr(shift,0,1); |
| 911 | if (ord('^')==94) { # ascii |
| 912 | return $char =~ /[\000-\037]/; |
| 913 | } |
| 914 | if (ord('^')==176) { # 37 |
| 915 | return $char =~ /[\000-\003\067\055-\057\026\005\045\013-\023\074\075\062\046\030\031\077\047\034-\037]/; |
| 916 | } |
| 917 | if (ord('^')==95 || ord('^')==106) { # 1047 || posix-bc |
| 918 | return $char =~ /[\000-\003\067\055-\057\026\005\025\013-\023\074\075\062\046\030\031\077\047\034-\037]/; |
| 919 | } |
| 920 | } |
| 921 | |
| 922 | sub Is_print_ascii { |
| 923 | my $char = substr(shift,0,1); |
| 924 | $char =~ /[ !"\#\$%&'()*+,\-.\/0-9:;<=>?\@A-Z[\\\]^_`a-z{|}~]/; |
| 925 | } |
| 926 | |
| 927 | sub Is_delete { |
| 928 | my $char = substr(shift,0,1); |
| 929 | if (ord('^')==94) { # ascii |
| 930 | return $char eq "\177"; |
| 931 | } |
| 932 | else { # ebcdic |
| 933 | return $char eq "\007"; |
| 934 | } |
| 935 | } |
| 936 | |
| 937 | sub Is_c1 { |
| 938 | my $char = substr(shift,0,1); |
| 939 | if (ord('^')==94) { # ascii |
| 940 | return $char =~ /[\200-\237]/; |
| 941 | } |
| 942 | if (ord('^')==176) { # 37 |
| 943 | return $char =~ /[\040-\044\025\006\027\050-\054\011\012\033\060\061\032\063-\066\010\070-\073\040\024\076\377]/; |
| 944 | } |
| 945 | if (ord('^')==95) { # 1047 |
| 946 | return $char =~ /[\040-\045\006\027\050-\054\011\012\033\060\061\032\063-\066\010\070-\073\040\024\076\377]/; |
| 947 | } |
| 948 | if (ord('^')==106) { # posix-bc |
| 949 | return $char =~ |
| 950 | /[\040-\045\006\027\050-\054\011\012\033\060\061\032\063-\066\010\070-\073\040\024\076\137]/; |
| 951 | } |
| 952 | } |
| 953 | |
| 954 | sub Is_latin_1 { |
| 955 | my $char = substr(shift,0,1); |
| 956 | if (ord('^')==94) { # ascii |
| 957 | return $char =~ /[\240-\377]/; |
| 958 | } |
| 959 | if (ord('^')==176) { # 37 |
| 960 | return $char =~ |
| 961 | /[\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]/; |
| 962 | } |
| 963 | if (ord('^')==95) { # 1047 |
| 964 | return $char =~ |
| 965 | /[\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]/; |
| 966 | } |
| 967 | if (ord('^')==106) { # posix-bc |
| 968 | return $char =~ |
| 969 | /[\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]/; |
| 970 | } |
| 971 | } |
| 972 | |
| 973 | Note however that only the C<Is_ascii_print()> sub is really independent |
| 974 | of coded character set. Another way to write C<Is_latin_1()> would be |
| 975 | to use the characters in the range explicitly: |
| 976 | |
| 977 | sub Is_latin_1 { |
| 978 | my $char = substr(shift,0,1); |
| 979 |