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d396a558 1=head1 NAME
2
3perlebcdic - Considerations for running Perl on EBCDIC platforms
4
5=head1 DESCRIPTION
6
7An exploration of some of the issues facing Perl programmers
8on EBCDIC based computers. We do not cover localization,
395f5a0c 9internationalization, or multi byte character set issues other
10than some discussion of UTF-8 and UTF-EBCDIC.
d396a558 11
12Portions that are still incomplete are marked with XXX.
13
e1b711da 14Perl used to work on EBCDIC machines, but there are now areas of the code where
15it doesn't. If you want to use Perl on an EBCDIC machine, please let us know
16by sending mail to perlbug@perl.org
17
d396a558 18=head1 COMMON CHARACTER CODE SETS
19
20=head2 ASCII
21
2bbc8d55 22The American Standard Code for Information Interchange (ASCII or US-ASCII) is a
23set of
d396a558 24integers running from 0 to 127 (decimal) that imply character
2bbc8d55 25interpretation by the display and other systems of computers.
51b5cecb 26The range 0..127 can be covered by setting the bits in a 7-bit binary
d396a558 27digit, hence the set is sometimes referred to as a "7-bit ASCII".
51b5cecb 28ASCII was described by the American National Standards Institute
d396a558 29document ANSI X3.4-1986. It was also described by ISO 646:1991
30(with localization for currency symbols). The full ASCII set is
31given in the table below as the first 128 elements. Languages that
32can be written adequately with the characters in ASCII include
33English, Hawaiian, Indonesian, Swahili and some Native American
34languages.
35
51b5cecb 36There are many character sets that extend the range of integers
37from 0..2**7-1 up to 2**8-1, or 8 bit bytes (octets if you prefer).
38One common one is the ISO 8859-1 character set.
39
d396a558 40=head2 ISO 8859
41
42The ISO 8859-$n are a collection of character code sets from the
43International Organization for Standardization (ISO) each of which
44adds characters to the ASCII set that are typically found in European
45languages many of which are based on the Roman, or Latin, alphabet.
46
47=head2 Latin 1 (ISO 8859-1)
48
49A particular 8-bit extension to ASCII that includes grave and acute
50accented Latin characters. Languages that can employ ISO 8859-1
51include all the languages covered by ASCII as well as Afrikaans,
52Albanian, Basque, Catalan, Danish, Faroese, Finnish, Norwegian,
3958b146 53Portuguese, Spanish, and Swedish. Dutch is covered albeit without
d396a558 54the ij ligature. French is covered too but without the oe ligature.
55German can use ISO 8859-1 but must do so without German-style
56quotation marks. This set is based on Western European extensions
57to ASCII and is commonly encountered in world wide web work.
58In IBM character code set identification terminology ISO 8859-1 is
51b5cecb 59also known as CCSID 819 (or sometimes 0819 or even 00819).
d396a558 60
61=head2 EBCDIC
62
395f5a0c 63The Extended Binary Coded Decimal Interchange Code refers to a
e1b711da 64large collection of single and multi byte coded character sets that are
65different from ASCII or ISO 8859-1 and are all slightly different from each
66other; they typically run on host computers. The EBCDIC encodings derive from
678 bit byte extensions of Hollerith punched card encodings. The layout on the
68cards was such that high bits were set for the upper and lower case alphabet
69characters [a-z] and [A-Z], but there were gaps within each Latin alphabet
70range.
d396a558 71
51b5cecb 72Some IBM EBCDIC character sets may be known by character code set
73identification numbers (CCSID numbers) or code page numbers. Leading
74zero digits in CCSID numbers within this document are insignificant.
75E.g. CCSID 0037 may be referred to as 37 in places.
76
2bbc8d55 77Perl can be compiled on platforms that run any of three commonly used EBCDIC
78character sets, listed below.
79
f4084e39 80=head2 The 13 variant characters
1e054b24 81
51b5cecb 82Among IBM EBCDIC character code sets there are 13 characters that
83are often mapped to different integer values. Those characters
84are known as the 13 "variant" characters and are:
d396a558 85
51b5cecb 86 \ [ ] { } ^ ~ ! # | $ @ `
d396a558 87
2bbc8d55 88When Perl is compiled for a platform, it looks at some of these characters to
89guess which EBCDIC character set the platform uses, and adapts itself
90accordingly to that platform. If the platform uses a character set that is not
91one of the three Perl knows about, Perl will either fail to compile, or
92mistakenly and silently choose one of the three.
93They are:
94
d396a558 95=head2 0037
96
97Character code set ID 0037 is a mapping of the ASCII plus Latin-1
98characters (i.e. ISO 8859-1) to an EBCDIC set. 0037 is used
51b5cecb 99in North American English locales on the OS/400 operating system
100that runs on AS/400 computers. CCSID 37 differs from ISO 8859-1
101in 237 places, in other words they agree on only 19 code point values.
d396a558 102
103=head2 1047
104
105Character code set ID 1047 is also a mapping of the ASCII plus
106Latin-1 characters (i.e. ISO 8859-1) to an EBCDIC set. 1047 is
395f5a0c 107used under Unix System Services for OS/390 or z/OS, and OpenEdition
108for VM/ESA. CCSID 1047 differs from CCSID 0037 in eight places.
d396a558 109
110=head2 POSIX-BC
111
112The EBCDIC code page in use on Siemens' BS2000 system is distinct from
1131047 and 0037. It is identified below as the POSIX-BC set.
114
64c66fb6 115=head2 Unicode code points versus EBCDIC code points
116
117In Unicode terminology a I<code point> is the number assigned to a
118character: for example, in EBCDIC the character "A" is usually assigned
119the number 193. In Unicode the character "A" is assigned the number 65.
120This causes a problem with the semantics of the pack/unpack "U", which
121are supposed to pack Unicode code points to characters and back to numbers.
122The problem is: which code points to use for code points less than 256?
123(for 256 and over there's no problem: Unicode code points are used)
124In EBCDIC, for the low 256 the EBCDIC code points are used. This
125means that the equivalences
126
127 pack("U", ord($character)) eq $character
128 unpack("U", $character) == ord $character
129
130will hold. (If Unicode code points were applied consistently over
131all the possible code points, pack("U",ord("A")) would in EBCDIC
132equal I<A with acute> or chr(101), and unpack("U", "A") would equal
13365, or I<non-breaking space>, not 193, or ord "A".)
134
dc4af4bb 135=head2 Remaining Perl Unicode problems in EBCDIC
136
137=over 4
138
139=item *
140
2bbc8d55 141Many of the remaining problems seem to be related to case-insensitive matching
dc4af4bb 142
143=item *
144
145The extensions Unicode::Collate and Unicode::Normalized are not
146supported under EBCDIC, likewise for the encoding pragma.
147
148=back
149
395f5a0c 150=head2 Unicode and UTF
151
2bbc8d55 152UTF stands for C<Unicode Transformation Format>.
153UTF-8 is an encoding of Unicode into a sequence of 8-bit byte chunks, based on
154ASCII and Latin-1.
155The length of a sequence required to represent a Unicode code point
156depends on the ordinal number of that code point,
157with larger numbers requiring more bytes.
158UTF-EBCDIC is like UTF-8, but based on EBCDIC.
159
fe749c9a 160You may see the term C<invariant> character or code point.
161This simply means that the character has the same numeric
162value when encoded as when not.
42bde815 163(Note that this is a very different concept from L</The 13 variant characters>
2bbc8d55 164mentioned above.)
fe749c9a 165For example, the ordinal value of 'A' is 193 in most EBCDIC code pages,
166and also is 193 when encoded in UTF-EBCDIC.
e1b711da 167All variant code points occupy at least two bytes when encoded.
fe749c9a 168In UTF-8, the code points corresponding to the lowest 128
169ordinal numbers (0 - 127: the ASCII characters) are invariant.
170In UTF-EBCDIC, there are 160 invariant characters.
2bbc8d55 171(If you care, the EBCDIC invariants are those characters
fe749c9a 172which have ASCII equivalents, plus those that correspond to
2bbc8d55 173the C1 controls (80..9f on ASCII platforms).)
fe749c9a 174
2bbc8d55 175A string encoded in UTF-EBCDIC may be longer (but never shorter) than
176one encoded in UTF-8.
395f5a0c 177
8704cfd1 178=head2 Using Encode
8f94de01 179
180Starting from Perl 5.8 you can use the standard new module Encode
2bbc8d55 181to translate from EBCDIC to Latin-1 code points.
182Encode knows about more EBCDIC character sets than Perl can currently
183be compiled to run on.
8f94de01 184
185 use Encode 'from_to';
186
187 my %ebcdic = ( 176 => 'cp37', 95 => 'cp1047', 106 => 'posix-bc' );
188
189 # $a is in EBCDIC code points
190 from_to($a, $ebcdic{ord '^'}, 'latin1');
191 # $a is ISO 8859-1 code points
192
193and from Latin-1 code points to EBCDIC code points
194
195 use Encode 'from_to';
196
197 my %ebcdic = ( 176 => 'cp37', 95 => 'cp1047', 106 => 'posix-bc' );
198
199 # $a is ISO 8859-1 code points
200 from_to($a, 'latin1', $ebcdic{ord '^'});
201 # $a is in EBCDIC code points
202
203For doing I/O it is suggested that you use the autotranslating features
204of PerlIO, see L<perluniintro>.
205
aa2b82fc 206Since version 5.8 Perl uses the new PerlIO I/O library. This enables
207you to use different encodings per IO channel. For example you may use
208
209 use Encode;
210 open($f, ">:encoding(ascii)", "test.ascii");
211 print $f "Hello World!\n";
212 open($f, ">:encoding(cp37)", "test.ebcdic");
213 print $f "Hello World!\n";
214 open($f, ">:encoding(latin1)", "test.latin1");
215 print $f "Hello World!\n";
216 open($f, ">:encoding(utf8)", "test.utf8");
217 print $f "Hello World!\n";
218
2bbc8d55 219to get four files containing "Hello World!\n" in ASCII, CP 37 EBCDIC,
220ISO 8859-1 (Latin-1) (in this example identical to ASCII since only ASCII
221characters were printed), and
222UTF-EBCDIC (in this example identical to normal EBCDIC since only characters
223that don't differ between EBCDIC and UTF-EBCDIC were printed). See the
aa2b82fc 224documentation of Encode::PerlIO for details.
225
226As the PerlIO layer uses raw IO (bytes) internally, all this totally
227ignores things like the type of your filesystem (ASCII or EBCDIC).
228
d396a558 229=head1 SINGLE OCTET TABLES
230
231The following tables list the ASCII and Latin 1 ordered sets including
232the subsets: C0 controls (0..31), ASCII graphics (32..7e), delete (7f),
233C1 controls (80..9f), and Latin-1 (a.k.a. ISO 8859-1) (a0..ff). In the
234table non-printing control character names as well as the Latin 1
235extensions to ASCII have been labelled with character names roughly
395f5a0c 236corresponding to I<The Unicode Standard, Version 3.0> albeit with
d396a558 237substitutions such as s/LATIN// and s/VULGAR// in all cases,
238s/CAPITAL LETTER// in some cases, and s/SMALL LETTER ([A-Z])/\l$1/
1e054b24 239in some other cases (the C<charnames> pragma names unfortunately do
240not list explicit names for the C0 or C1 control characters). The
241"names" of the C1 control set (128..159 in ISO 8859-1) listed here are
242somewhat arbitrary. The differences between the 0037 and 1047 sets are
243flagged with ***. The differences between the 1047 and POSIX-BC sets
244are flagged with ###. All ord() numbers listed are decimal. If you
245would rather see this table listing octal values then run the table
246(that is, the pod version of this document since this recipe may not
247work with a pod2_other_format translation) through:
d396a558 248
249=over 4
250
251=item recipe 0
252
253=back
254
84f709e7 255 perl -ne 'if(/(.{33})(\d+)\s+(\d+)\s+(\d+)\s+(\d+)/)' \
256 -e '{printf("%s%-9o%-9o%-9o%o\n",$1,$2,$3,$4,$5)}' perlebcdic.pod
395f5a0c 257
258If you want to retain the UTF-x code points then in script form you
259might want to write:
260
261=over 4
262
263=item recipe 1
264
265=back
266
84f709e7 267 open(FH,"<perlebcdic.pod") or die "Could not open perlebcdic.pod: $!";
268 while (<FH>) {
269 if (/(.{33})(\d+)\s+(\d+)\s+(\d+)\s+(\d+)\s+(\d+)\.?(\d*)\s+(\d+)\.?(\d*)/) {
270 if ($7 ne '' && $9 ne '') {
271 printf("%s%-9o%-9o%-9o%-9o%-3o.%-5o%-3o.%o\n",$1,$2,$3,$4,$5,$6,$7,$8,$9);
272 }
273 elsif ($7 ne '') {
274 printf("%s%-9o%-9o%-9o%-9o%-3o.%-5o%o\n",$1,$2,$3,$4,$5,$6,$7,$8);
275 }
276 else {
277 printf("%s%-9o%-9o%-9o%-9o%-9o%o\n",$1,$2,$3,$4,$5,$6,$8);
395f5a0c 278 }
279 }
280 }
d396a558 281
282If you would rather see this table listing hexadecimal values then
283run the table through:
284
285=over 4
286
395f5a0c 287=item recipe 2
d396a558 288
289=back
290
84f709e7 291 perl -ne 'if(/(.{33})(\d+)\s+(\d+)\s+(\d+)\s+(\d+)/)' \
292 -e '{printf("%s%-9X%-9X%-9X%X\n",$1,$2,$3,$4,$5)}' perlebcdic.pod
395f5a0c 293
294Or, in order to retain the UTF-x code points in hexadecimal:
295
296=over 4
297
298=item recipe 3
299
300=back
301
84f709e7 302 open(FH,"<perlebcdic.pod") or die "Could not open perlebcdic.pod: $!";
395f5a0c 303 while (<FH>) {
84f709e7 304 if (/(.{33})(\d+)\s+(\d+)\s+(\d+)\s+(\d+)\s+(\d+)\.?(\d*)\s+(\d+)\.?(\d*)/) {
305 if ($7 ne '' && $9 ne '') {
306 printf("%s%-9X%-9X%-9X%-9X%-2X.%-6X%-2X.%X\n",$1,$2,$3,$4,$5,$6,$7,$8,$9);
395f5a0c 307 }
84f709e7 308 elsif ($7 ne '') {
309 printf("%s%-9X%-9X%-9X%-9X%-2X.%-6X%X\n",$1,$2,$3,$4,$5,$6,$7,$8);
395f5a0c 310 }
311 else {
84f709e7 312 printf("%s%-9X%-9X%-9X%-9X%-9X%X\n",$1,$2,$3,$4,$5,$6,$8);
395f5a0c 313 }
314 }
315 }
316
317
318 incomp- incomp-
319 8859-1 lete lete
320 chr 0819 0037 1047 POSIX-BC UTF-8 UTF-EBCDIC
321 ------------------------------------------------------------------------------------
322 <NULL> 0 0 0 0 0 0
323 <START OF HEADING> 1 1 1 1 1 1
324 <START OF TEXT> 2 2 2 2 2 2
325 <END OF TEXT> 3 3 3 3 3 3
326 <END OF TRANSMISSION> 4 55 55 55 4 55
327 <ENQUIRY> 5 45 45 45 5 45
328 <ACKNOWLEDGE> 6 46 46 46 6 46
329 <BELL> 7 47 47 47 7 47
330 <BACKSPACE> 8 22 22 22 8 22
331 <HORIZONTAL TABULATION> 9 5 5 5 9 5
332 <LINE FEED> 10 37 21 21 10 21 ***
333 <VERTICAL TABULATION> 11 11 11 11 11 11
334 <FORM FEED> 12 12 12 12 12 12
335 <CARRIAGE RETURN> 13 13 13 13 13 13
336 <SHIFT OUT> 14 14 14 14 14 14
337 <SHIFT IN> 15 15 15 15 15 15
338 <DATA LINK ESCAPE> 16 16 16 16 16 16
339 <DEVICE CONTROL ONE> 17 17 17 17 17 17
340 <DEVICE CONTROL TWO> 18 18 18 18 18 18
341 <DEVICE CONTROL THREE> 19 19 19 19 19 19
342 <DEVICE CONTROL FOUR> 20 60 60 60 20 60
343 <NEGATIVE ACKNOWLEDGE> 21 61 61 61 21 61
344 <SYNCHRONOUS IDLE> 22 50 50 50 22 50
345 <END OF TRANSMISSION BLOCK> 23 38 38 38 23 38
346 <CANCEL> 24 24 24 24 24 24
347 <END OF MEDIUM> 25 25 25 25 25 25
348 <SUBSTITUTE> 26 63 63 63 26 63
349 <ESCAPE> 27 39 39 39 27 39
350 <FILE SEPARATOR> 28 28 28 28 28 28
351 <GROUP SEPARATOR> 29 29 29 29 29 29
352 <RECORD SEPARATOR> 30 30 30 30 30 30
353 <UNIT SEPARATOR> 31 31 31 31 31 31
354 <SPACE> 32 64 64 64 32 64
355 ! 33 90 90 90 33 90
356 " 34 127 127 127 34 127
357 # 35 123 123 123 35 123
358 $ 36 91 91 91 36 91
359 % 37 108 108 108 37 108
360 & 38 80 80 80 38 80
361 ' 39 125 125 125 39 125
362 ( 40 77 77 77 40 77
363 ) 41 93 93 93 41 93
364 * 42 92 92 92 42 92
365 + 43 78 78 78 43 78
366 , 44 107 107 107 44 107
367 - 45 96 96 96 45 96
368 . 46 75 75 75 46 75
369 / 47 97 97 97 47 97
370 0 48 240 240 240 48 240
371 1 49 241 241 241 49 241
372 2 50 242 242 242 50 242
373 3 51 243 243 243 51 243
374 4 52 244 244 244 52 244
375 5 53 245 245 245 53 245
376 6 54 246 246 246 54 246
377 7 55 247 247 247 55 247
378 8 56 248 248 248 56 248
379 9 57 249 249 249 57 249
380 : 58 122 122 122 58 122
381 ; 59 94 94 94 59 94
382 < 60 76 76 76 60 76
383 = 61 126 126 126 61 126
384 > 62 110 110 110 62 110
385 ? 63 111 111 111 63 111
386 @ 64 124 124 124 64 124
387 A 65 193 193 193 65 193
388 B 66 194 194 194 66 194
389 C 67 195 195 195 67 195
390 D 68 196 196 196 68 196
391 E 69 197 197 197 69 197
392 F 70 198 198 198 70 198
393 G 71 199 199 199 71 199
394 H 72 200 200 200 72 200
395 I 73 201 201 201 73 201
396 J 74 209 209 209 74 209
397 K 75 210 210 210 75 210
398 L 76 211 211 211 76 211
399 M 77 212 212 212 77 212
400 N 78 213 213 213 78 213
401 O 79 214 214 214 79 214
402 P 80 215 215 215 80 215
403 Q 81 216 216 216 81 216
404 R 82 217 217 217 82 217
405 S 83 226 226 226 83 226
406 T 84 227 227 227 84 227
407 U 85 228 228 228 85 228
408 V 86 229 229 229 86 229
409 W 87 230 230 230 87 230
410 X 88 231 231 231 88 231
411 Y 89 232 232 232 89 232
412 Z 90 233 233 233 90 233
413 [ 91 186 173 187 91 173 *** ###
414 \ 92 224 224 188 92 224 ###
415 ] 93 187 189 189 93 189 ***
416 ^ 94 176 95 106 94 95 *** ###
417 _ 95 109 109 109 95 109
418 ` 96 121 121 74 96 121 ###
419 a 97 129 129 129 97 129
420 b 98 130 130 130 98 130
421 c 99 131 131 131 99 131
422 d 100 132 132 132 100 132
423 e 101 133 133 133 101 133
424 f 102 134 134 134 102 134
425 g 103 135 135 135 103 135
426 h 104 136 136 136 104 136
427 i 105 137 137 137 105 137
428 j 106 145 145 145 106 145
429 k 107 146 146 146 107 146
430 l 108 147 147 147 108 147
431 m 109 148 148 148 109 148
432 n 110 149 149 149 110 149
433 o 111 150 150 150 111 150
434 p 112 151 151 151 112 151
435 q 113 152 152 152 113 152
436 r 114 153 153 153 114 153
437 s 115 162 162 162 115 162
438 t 116 163 163 163 116 163
439 u 117 164 164 164 117 164
440 v 118 165 165 165 118 165
441 w 119 166 166 166 119 166
442 x 120 167 167 167 120 167
443 y 121 168 168 168 121 168
444 z 122 169 169 169 122 169
445 { 123 192 192 251 123 192 ###
446 | 124 79 79 79 124 79
447 } 125 208 208 253 125 208 ###
448 ~ 126 161 161 255 126 161 ###
449 <DELETE> 127 7 7 7 127 7
450 <C1 0> 128 32 32 32 194.128 32
451 <C1 1> 129 33 33 33 194.129 33
452 <C1 2> 130 34 34 34 194.130 34
453 <C1 3> 131 35 35 35 194.131 35
454 <C1 4> 132 36 36 36 194.132 36
455 <C1 5> 133 21 37 37 194.133 37 ***
456 <C1 6> 134 6 6 6 194.134 6
457 <C1 7> 135 23 23 23 194.135 23
458 <C1 8> 136 40 40 40 194.136 40
459 <C1 9> 137 41 41 41 194.137 41
460 <C1 10> 138 42 42 42 194.138 42
461 <C1 11> 139 43 43 43 194.139 43
462 <C1 12> 140 44 44 44 194.140 44
463 <C1 13> 141 9 9 9 194.141 9
464 <C1 14> 142 10 10 10 194.142 10
465 <C1 15> 143 27 27 27 194.143 27
466 <C1 16> 144 48 48 48 194.144 48
467 <C1 17> 145 49 49 49 194.145 49
468 <C1 18> 146 26 26 26 194.146 26
469 <C1 19> 147 51 51 51 194.147 51
470 <C1 20> 148 52 52 52 194.148 52
471 <C1 21> 149 53 53 53 194.149 53
472 <C1 22> 150 54 54 54 194.150 54
473 <C1 23> 151 8 8 8 194.151 8
474 <C1 24> 152 56 56 56 194.152 56
475 <C1 25> 153 57 57 57 194.153 57
476 <C1 26> 154 58 58 58 194.154 58
477 <C1 27> 155 59 59 59 194.155 59
478 <C1 28> 156 4 4 4 194.156 4
479 <C1 29> 157 20 20 20 194.157 20
480 <C1 30> 158 62 62 62 194.158 62
481 <C1 31> 159 255 255 95 194.159 255 ###
482 <NON-BREAKING SPACE> 160 65 65 65 194.160 128.65
483 <INVERTED EXCLAMATION MARK> 161 170 170 170 194.161 128.66
484 <CENT SIGN> 162 74 74 176 194.162 128.67 ###
485 <POUND SIGN> 163 177 177 177 194.163 128.68
486 <CURRENCY SIGN> 164 159 159 159 194.164 128.69
487 <YEN SIGN> 165 178 178 178 194.165 128.70
488 <BROKEN BAR> 166 106 106 208 194.166 128.71 ###
489 <SECTION SIGN> 167 181 181 181 194.167 128.72
490 <DIAERESIS> 168 189 187 121 194.168 128.73 *** ###
491 <COPYRIGHT SIGN> 169 180 180 180 194.169 128.74
492 <FEMININE ORDINAL INDICATOR> 170 154 154 154 194.170 128.81
493 <LEFT POINTING GUILLEMET> 171 138 138 138 194.171 128.82
494 <NOT SIGN> 172 95 176 186 194.172 128.83 *** ###
495 <SOFT HYPHEN> 173 202 202 202 194.173 128.84
496 <REGISTERED TRADE MARK SIGN> 174 175 175 175 194.174 128.85
497 <MACRON> 175 188 188 161 194.175 128.86 ###
498 <DEGREE SIGN> 176 144 144 144 194.176 128.87
499 <PLUS-OR-MINUS SIGN> 177 143 143 143 194.177 128.88
500 <SUPERSCRIPT TWO> 178 234 234 234 194.178 128.89
501 <SUPERSCRIPT THREE> 179 250 250 250 194.179 128.98
502 <ACUTE ACCENT> 180 190 190 190 194.180 128.99
503 <MICRO SIGN> 181 160 160 160 194.181 128.100
504 <PARAGRAPH SIGN> 182 182 182 182 194.182 128.101
505 <MIDDLE DOT> 183 179 179 179 194.183 128.102
506 <CEDILLA> 184 157 157 157 194.184 128.103
507 <SUPERSCRIPT ONE> 185 218 218 218 194.185 128.104
508 <MASC. ORDINAL INDICATOR> 186 155 155 155 194.186 128.105
509 <RIGHT POINTING GUILLEMET> 187 139 139 139 194.187 128.106
510 <FRACTION ONE QUARTER> 188 183 183 183 194.188 128.112
511 <FRACTION ONE HALF> 189 184 184 184 194.189 128.113
512 <FRACTION THREE QUARTERS> 190 185 185 185 194.190 128.114
513 <INVERTED QUESTION MARK> 191 171 171 171 194.191 128.115
514 <A WITH GRAVE> 192 100 100 100 195.128 138.65
515 <A WITH ACUTE> 193 101 101 101 195.129 138.66
516 <A WITH CIRCUMFLEX> 194 98 98 98 195.130 138.67
517 <A WITH TILDE> 195 102 102 102 195.131 138.68
518 <A WITH DIAERESIS> 196 99 99 99 195.132 138.69
519 <A WITH RING ABOVE> 197 103 103 103 195.133 138.70
520 <CAPITAL LIGATURE AE> 198 158 158 158 195.134 138.71
521 <C WITH CEDILLA> 199 104 104 104 195.135 138.72
522 <E WITH GRAVE> 200 116 116 116 195.136 138.73
523 <E WITH ACUTE> 201 113 113 113 195.137 138.74
524 <E WITH CIRCUMFLEX> 202 114 114 114 195.138 138.81
525 <E WITH DIAERESIS> 203 115 115 115 195.139 138.82
526 <I WITH GRAVE> 204 120 120 120 195.140 138.83
527 <I WITH ACUTE> 205 117 117 117 195.141 138.84
528 <I WITH CIRCUMFLEX> 206 118 118 118 195.142 138.85
529 <I WITH DIAERESIS> 207 119 119 119 195.143 138.86
530 <CAPITAL LETTER ETH> 208 172 172 172 195.144 138.87
531 <N WITH TILDE> 209 105 105 105 195.145 138.88
532 <O WITH GRAVE> 210 237 237 237 195.146 138.89
533 <O WITH ACUTE> 211 238 238 238 195.147 138.98
534 <O WITH CIRCUMFLEX> 212 235 235 235 195.148 138.99
535 <O WITH TILDE> 213 239 239 239 195.149 138.100
536 <O WITH DIAERESIS> 214 236 236 236 195.150 138.101
537 <MULTIPLICATION SIGN> 215 191 191 191 195.151 138.102
538 <O WITH STROKE> 216 128 128 128 195.152 138.103
539 <U WITH GRAVE> 217 253 253 224 195.153 138.104 ###
540 <U WITH ACUTE> 218 254 254 254 195.154 138.105
541 <U WITH CIRCUMFLEX> 219 251 251 221 195.155 138.106 ###
542 <U WITH DIAERESIS> 220 252 252 252 195.156 138.112
543 <Y WITH ACUTE> 221 173 186 173 195.157 138.113 *** ###
544 <CAPITAL LETTER THORN> 222 174 174 174 195.158 138.114
545 <SMALL LETTER SHARP S> 223 89 89 89 195.159 138.115
546 <a WITH GRAVE> 224 68 68 68 195.160 139.65
547 <a WITH ACUTE> 225 69 69 69 195.161 139.66
548 <a WITH CIRCUMFLEX> 226 66 66 66 195.162 139.67
549 <a WITH TILDE> 227 70 70 70 195.163 139.68
550 <a WITH DIAERESIS> 228 67 67 67 195.164 139.69
551 <a WITH RING ABOVE> 229 71 71 71 195.165 139.70
552 <SMALL LIGATURE ae> 230 156 156 156 195.166 139.71
553 <c WITH CEDILLA> 231 72 72 72 195.167 139.72
554 <e WITH GRAVE> 232 84 84 84 195.168 139.73
555 <e WITH ACUTE> 233 81 81 81 195.169 139.74
556 <e WITH CIRCUMFLEX> 234 82 82 82 195.170 139.81
557 <e WITH DIAERESIS> 235 83 83 83 195.171 139.82
558 <i WITH GRAVE> 236 88 88 88 195.172 139.83
559 <i WITH ACUTE> 237 85 85 85 195.173 139.84
560 <i WITH CIRCUMFLEX> 238 86 86 86 195.174 139.85
561 <i WITH DIAERESIS> 239 87 87 87 195.175 139.86
562 <SMALL LETTER eth> 240 140 140 140 195.176 139.87
563 <n WITH TILDE> 241 73 73 73 195.177 139.88
564 <o WITH GRAVE> 242 205 205 205 195.178 139.89
565 <o WITH ACUTE> 243 206 206 206 195.179 139.98
566 <o WITH CIRCUMFLEX> 244 203 203 203 195.180 139.99
567 <o WITH TILDE> 245 207 207 207 195.181 139.100
568 <o WITH DIAERESIS> 246 204 204 204 195.182 139.101
569 <DIVISION SIGN> 247 225 225 225 195.183 139.102
570 <o WITH STROKE> 248 112 112 112 195.184 139.103
571 <u WITH GRAVE> 249 221 221 192 195.185 139.104 ###
572 <u WITH ACUTE> 250 222 222 222 195.186 139.105
573 <u WITH CIRCUMFLEX> 251 219 219 219 195.187 139.106
574 <u WITH DIAERESIS> 252 220 220 220 195.188 139.112
575 <y WITH ACUTE> 253 141 141 141 195.189 139.113
576 <SMALL LETTER thorn> 254 142 142 142 195.190 139.114
577 <y WITH DIAERESIS> 255 223 223 223 195.191 139.115
d396a558 578
579If you would rather see the above table in CCSID 0037 order rather than
580ASCII + Latin-1 order then run the table through:
581
582=over 4
583
395f5a0c 584=item recipe 4
d396a558 585
586=back
587
84f709e7 588 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}/)'\
589 -e '{push(@l,$_)}' \
590 -e 'END{print map{$_->[0]}' \
591 -e ' sort{$a->[1] <=> $b->[1]}' \
592 -e ' map{[$_,substr($_,42,3)]}@l;}' perlebcdic.pod
d396a558 593
594If you would rather see it in CCSID 1047 order then change the digit
59542 in the last line to 51, like this:
596
597=over 4
598
395f5a0c 599=item recipe 5
d396a558 600
601=back
602
84f709e7 603 perl -ne 'if(/.{33}\d{1,3}\s{6,8}\d{1,3}\s{6,8}\d{1,3}\s{6,8}\d{1,3}/)'\
604 -e '{push(@l,$_)}' \
605 -e 'END{print map{$_->[0]}' \
606 -e ' sort{$a->[1] <=> $b->[1]}' \
607 -e ' map{[$_,substr($_,51,3)]}@l;}' perlebcdic.pod
d396a558 608
609If you would rather see it in POSIX-BC order then change the digit
61051 in the last line to 60, like this:
611
612=over 4
613
395f5a0c 614=item recipe 6
d396a558 615
616=back
617
84f709e7 618 perl -ne 'if(/.{33}\d{1,3}\s{6,8}\d{1,3}\s{6,8}\d{1,3}\s{6,8}\d{1,3}/)'\
619 -e '{push(@l,$_)}' \
620 -e 'END{print map{$_->[0]}' \
621 -e ' sort{$a->[1] <=> $b->[1]}' \
622 -e ' map{[$_,substr($_,60,3)]}@l;}' perlebcdic.pod
d396a558 623
624
625=head1 IDENTIFYING CHARACTER CODE SETS
626
627To determine the character set you are running under from perl one
628could use the return value of ord() or chr() to test one or more
629character values. For example:
630
84f709e7 631 $is_ascii = "A" eq chr(65);
632 $is_ebcdic = "A" eq chr(193);
d396a558 633
51b5cecb 634Also, "\t" is a C<HORIZONTAL TABULATION> character so that:
d396a558 635
84f709e7 636 $is_ascii = ord("\t") == 9;
637 $is_ebcdic = ord("\t") == 5;
d396a558 638
639To distinguish EBCDIC code pages try looking at one or more of
640the characters that differ between them. For example:
641
84f709e7 642 $is_ebcdic_37 = "\n" eq chr(37);
643 $is_ebcdic_1047 = "\n" eq chr(21);
d396a558 644
645Or better still choose a character that is uniquely encoded in any
646of the code sets, e.g.:
647
84f709e7 648 $is_ascii = ord('[') == 91;
649 $is_ebcdic_37 = ord('[') == 186;
650 $is_ebcdic_1047 = ord('[') == 173;
651 $is_ebcdic_POSIX_BC = ord('[') == 187;
d396a558 652
653However, it would be unwise to write tests such as:
654
84f709e7 655 $is_ascii = "\r" ne chr(13); # WRONG
656 $is_ascii = "\n" ne chr(10); # ILL ADVISED
d396a558 657
2bbc8d55 658Obviously the first of these will fail to distinguish most ASCII platforms
659from either a CCSID 0037, a 1047, or a POSIX-BC EBCDIC platform since "\r" eq
84f709e7 660chr(13) under all of those coded character sets. But note too that
661because "\n" is chr(13) and "\r" is chr(10) on the MacIntosh (which is an
2bbc8d55 662ASCII platform) the second C<$is_ascii> test will lead to trouble there.
d396a558 663
84f709e7 664To determine whether or not perl was built under an EBCDIC
d396a558 665code page you can use the Config module like so:
666
667 use Config;
84f709e7 668 $is_ebcdic = $Config{'ebcdic'} eq 'define';
d396a558 669
670=head1 CONVERSIONS
671
1e054b24 672=head2 tr///
673
d396a558 674In order to convert a string of characters from one character set to
675another a simple list of numbers, such as in the right columns in the
676above table, along with perl's tr/// operator is all that is needed.
677The data in the table are in ASCII order hence the EBCDIC columns
678provide easy to use ASCII to EBCDIC operations that are also easily
679reversed.
680
84f709e7 681For example, to convert ASCII to code page 037 take the output of the second
682column from the output of recipe 0 (modified to add \\ characters) and use
d5d9880c 683it in tr/// like so:
d396a558 684
84f709e7 685 $cp_037 =
686 '\000\001\002\003\234\011\206\177\227\215\216\013\014\015\016\017' .
687 '\020\021\022\023\235\205\010\207\030\031\222\217\034\035\036\037' .
688 '\200\201\202\203\204\012\027\033\210\211\212\213\214\005\006\007' .
689 '\220\221\026\223\224\225\226\004\230\231\232\233\024\025\236\032' .
690 '\040\240\342\344\340\341\343\345\347\361\242\056\074\050\053\174' .
691 '\046\351\352\353\350\355\356\357\354\337\041\044\052\051\073\254' .
692 '\055\057\302\304\300\301\303\305\307\321\246\054\045\137\076\077' .
693 '\370\311\312\313\310\315\316\317\314\140\072\043\100\047\075\042' .
694 '\330\141\142\143\144\145\146\147\150\151\253\273\360\375\376\261' .
695 '\260\152\153\154\155\156\157\160\161\162\252\272\346\270\306\244' .
696 '\265\176\163\164\165\166\167\170\171\172\241\277\320\335\336\256' .
697 '\136\243\245\267\251\247\266\274\275\276\133\135\257\250\264\327' .
698 '\173\101\102\103\104\105\106\107\110\111\255\364\366\362\363\365' .
699 '\175\112\113\114\115\116\117\120\121\122\271\373\374\371\372\377' .
700 '\134\367\123\124\125\126\127\130\131\132\262\324\326\322\323\325' .
701 '\060\061\062\063\064\065\066\067\070\071\263\333\334\331\332\237' ;
d396a558 702
703 my $ebcdic_string = $ascii_string;
d7449b02 704 eval '$ebcdic_string =~ tr/' . $cp_037 . '/\000-\377/';
d396a558 705
0be03469 706To convert from EBCDIC 037 to ASCII just reverse the order of the tr///
d396a558 707arguments like so:
708
709 my $ascii_string = $ebcdic_string;
d7449b02 710 eval '$ascii_string =~ tr/\000-\377/' . $cp_037 . '/';
d5d9880c 711
712Similarly one could take the output of the third column from recipe 0 to
713obtain a C<$cp_1047> table. The fourth column of the output from recipe
7140 could provide a C<$cp_posix_bc> table suitable for transcoding as well.
1e054b24 715
716=head2 iconv
d396a558 717
d5d9880c 718XPG operability often implies the presence of an I<iconv> utility
d396a558 719available from the shell or from the C library. Consult your system's
720documentation for information on iconv.
721
3958b146 722On OS/390 or z/OS see the iconv(1) manpage. One way to invoke the iconv
d396a558 723shell utility from within perl would be to:
724
395f5a0c 725 # OS/390 or z/OS example
84f709e7 726 $ascii_data = `echo '$ebcdic_data'| iconv -f IBM-1047 -t ISO8859-1`
d396a558 727
728or the inverse map:
729
395f5a0c 730 # OS/390 or z/OS example
84f709e7 731 $ebcdic_data = `echo '$ascii_data'| iconv -f ISO8859-1 -t IBM-1047`
d396a558 732
d396a558 733For other perl based conversion options see the Convert::* modules on CPAN.
734
1e054b24 735=head2 C RTL
736
395f5a0c 737The OS/390 and z/OS C run time libraries provide _atoe() and _etoa() functions.
1e054b24 738
d396a558 739=head1 OPERATOR DIFFERENCES
740
741The C<..> range operator treats certain character ranges with
2bbc8d55 742care on EBCDIC platforms. For example the following array
743will have twenty six elements on either an EBCDIC platform
744or an ASCII platform:
d396a558 745
84f709e7 746 @alphabet = ('A'..'Z'); # $#alphabet == 25
d396a558 747
748The bitwise operators such as & ^ | may return different results
749when operating on string or character data in a perl program running
2bbc8d55 750on an EBCDIC platform than when run on an ASCII platform. Here is
d396a558 751an example adapted from the one in L<perlop>:
752
753 # EBCDIC-based examples
84f709e7 754 print "j p \n" ^ " a h"; # prints "JAPH\n"
755 print "JA" | " ph\n"; # prints "japh\n"
756 print "JAPH\nJunk" & "\277\277\277\277\277"; # prints "japh\n";
757 print 'p N$' ^ " E<H\n"; # prints "Perl\n";
d396a558 758
759An interesting property of the 32 C0 control characters
760in the ASCII table is that they can "literally" be constructed
51b5cecb 761as control characters in perl, e.g. C<(chr(0) eq "\c@")>
2bbc8d55 762C<(chr(1) eq "\cA")>, and so on. Perl on EBCDIC platforms has been
51b5cecb 763ported to take "\c@" to chr(0) and "\cA" to chr(1) as well, but the
d396a558 764thirty three characters that result depend on which code page you are
765using. The table below uses the character names from the previous table
51b5cecb 766but with substitutions such as s/START OF/S.O./; s/END OF /E.O./;
d396a558 767s/TRANSMISSION/TRANS./; s/TABULATION/TAB./; s/VERTICAL/VERT./;
768s/HORIZONTAL/HORIZ./; s/DEVICE CONTROL/D.C./; s/SEPARATOR/SEP./;
769s/NEGATIVE ACKNOWLEDGE/NEG. ACK./;. The POSIX-BC and 1047 sets are
770identical throughout this range and differ from the 0037 set at only
51b5cecb 771one spot (21 decimal). Note that the C<LINE FEED> character
2bbc8d55 772may be generated by "\cJ" on ASCII platforms but by "\cU" on 1047 or POSIX-BC
773platforms and cannot be generated as a C<"\c.letter."> control character on
7740037 platforms. Note also that "\c\\" maps to two characters
d396a558 775not one.
776
777 chr ord 8859-1 0037 1047 && POSIX-BC
778 ------------------------------------------------------------------------
779 "\c?" 127 <DELETE> " " ***><
780 "\c@" 0 <NULL> <NULL> <NULL> ***><
781 "\cA" 1 <S.O. HEADING> <S.O. HEADING> <S.O. HEADING>
782 "\cB" 2 <S.O. TEXT> <S.O. TEXT> <S.O. TEXT>
783 "\cC" 3 <E.O. TEXT> <E.O. TEXT> <E.O. TEXT>
784 "\cD" 4 <E.O. TRANS.> <C1 28> <C1 28>
785 "\cE" 5 <ENQUIRY> <HORIZ. TAB.> <HORIZ. TAB.>
786 "\cF" 6 <ACKNOWLEDGE> <C1 6> <C1 6>
787 "\cG" 7 <BELL> <DELETE> <DELETE>
788 "\cH" 8 <BACKSPACE> <C1 23> <C1 23>
789 "\cI" 9 <HORIZ. TAB.> <C1 13> <C1 13>
790 "\cJ" 10 <LINE FEED> <C1 14> <C1 14>
791 "\cK" 11 <VERT. TAB.> <VERT. TAB.> <VERT. TAB.>
792 "\cL" 12 <FORM FEED> <FORM FEED> <FORM FEED>
793 "\cM" 13 <CARRIAGE RETURN> <CARRIAGE RETURN> <CARRIAGE RETURN>
794 "\cN" 14 <SHIFT OUT> <SHIFT OUT> <SHIFT OUT>
795 "\cO" 15 <SHIFT IN> <SHIFT IN> <SHIFT IN>
796 "\cP" 16 <DATA LINK ESCAPE> <DATA LINK ESCAPE> <DATA LINK ESCAPE>
797 "\cQ" 17 <D.C. ONE> <D.C. ONE> <D.C. ONE>
798 "\cR" 18 <D.C. TWO> <D.C. TWO> <D.C. TWO>
799 "\cS" 19 <D.C. THREE> <D.C. THREE> <D.C. THREE>
800 "\cT" 20 <D.C. FOUR> <C1 29> <C1 29>
801 "\cU" 21 <NEG. ACK.> <C1 5> <LINE FEED> ***
802 "\cV" 22 <SYNCHRONOUS IDLE> <BACKSPACE> <BACKSPACE>
803 "\cW" 23 <E.O. TRANS. BLOCK> <C1 7> <C1 7>
804 "\cX" 24 <CANCEL> <CANCEL> <CANCEL>
805 "\cY" 25 <E.O. MEDIUM> <E.O. MEDIUM> <E.O. MEDIUM>
806 "\cZ" 26 <SUBSTITUTE> <C1 18> <C1 18>
807 "\c[" 27 <ESCAPE> <C1 15> <C1 15>
808 "\c\\" 28 <FILE SEP.>\ <FILE SEP.>\ <FILE SEP.>\
809 "\c]" 29 <GROUP SEP.> <GROUP SEP.> <GROUP SEP.>
810 "\c^" 30 <RECORD SEP.> <RECORD SEP.> <RECORD SEP.> ***><
811 "\c_" 31 <UNIT SEP.> <UNIT SEP.> <UNIT SEP.> ***><
812
813
814=head1 FUNCTION DIFFERENCES
815
816=over 8
817
818=item chr()
819
820chr() must be given an EBCDIC code number argument to yield a desired
2bbc8d55 821character return value on an EBCDIC platform. For example:
d396a558 822
84f709e7 823 $CAPITAL_LETTER_A = chr(193);
d396a558 824
825=item ord()
826
2bbc8d55 827ord() will return EBCDIC code number values on an EBCDIC platform.
d396a558 828For example:
829
84f709e7 830 $the_number_193 = ord("A");
d396a558 831
832=item pack()
833
834The c and C templates for pack() are dependent upon character set
835encoding. Examples of usage on EBCDIC include:
836
837 $foo = pack("CCCC",193,194,195,196);
838 # $foo eq "ABCD"
84f709e7 839 $foo = pack("C4",193,194,195,196);
d396a558 840 # same thing
841
842 $foo = pack("ccxxcc",193,194,195,196);
843 # $foo eq "AB\0\0CD"
844
845=item print()
846
847One must be careful with scalars and strings that are passed to
848print that contain ASCII encodings. One common place
849for this to occur is in the output of the MIME type header for
850CGI script writing. For example, many perl programming guides
851recommend something similar to:
852
853 print "Content-type:\ttext/html\015\012\015\012";
854 # this may be wrong on EBCDIC
855
395f5a0c 856Under the IBM OS/390 USS Web Server or WebSphere on z/OS for example
857you should instead write that as:
d396a558 858
859 print "Content-type:\ttext/html\r\n\r\n"; # OK for DGW et alia
860
861That is because the translation from EBCDIC to ASCII is done
862by the web server in this case (such code will not be appropriate for
863the Macintosh however). Consult your web server's documentation for
864further details.
865
866=item printf()
867
868The formats that can convert characters to numbers and vice versa
869will be different from their ASCII counterparts when executed
2bbc8d55 870on an EBCDIC platform. Examples include:
d396a558 871
872 printf("%c%c%c",193,194,195); # prints ABC
873
874=item sort()
875
876EBCDIC sort results may differ from ASCII sort results especially for
877mixed case strings. This is discussed in more detail below.
878
879=item sprintf()
880
881See the discussion of printf() above. An example of the use
882of sprintf would be:
883
84f709e7 884 $CAPITAL_LETTER_A = sprintf("%c",193);
d396a558 885
886=item unpack()
887
888See the discussion of pack() above.
889
890=back
891
892=head1 REGULAR EXPRESSION DIFFERENCES
893
894As of perl 5.005_03 the letter range regular expression such as
895[A-Z] and [a-z] have been especially coded to not pick up gap
b3b6085d 896characters. For example, characters such as E<ocirc> C<o WITH CIRCUMFLEX>
897that lie between I and J would not be matched by the
1b2d223b 898regular expression range C</[H-K]/>. This works in
899the other direction, too, if either of the range end points is
900explicitly numeric: C<[\x89-\x91]> will match C<\x8e>, even
901though C<\x89> is C<i> and C<\x91 > is C<j>, and C<\x8e>
902is a gap character from the alphabetic viewpoint.
51b5cecb 903
904If you do want to match the alphabet gap characters in a single octet
d396a558 905regular expression try matching the hex or octal code such
2bbc8d55 906as C</\313/> on EBCDIC or C</\364/> on ASCII platforms to
51b5cecb 907have your regular expression match C<o WITH CIRCUMFLEX>.
d396a558 908
51b5cecb 909Another construct to be wary of is the inappropriate use of hex or
d396a558 910octal constants in regular expressions. Consider the following
911set of subs:
912
913 sub is_c0 {
914 my $char = substr(shift,0,1);
915 $char =~ /[\000-\037]/;
916 }
917
918 sub is_print_ascii {
919 my $char = substr(shift,0,1);
920 $char =~ /[\040-\176]/;
921 }
922
923 sub is_delete {
924 my $char = substr(shift,0,1);
925 $char eq "\177";
926 }
927
928 sub is_c1 {
929 my $char = substr(shift,0,1);
930 $char =~ /[\200-\237]/;
931 }
932
933 sub is_latin_1 {
934 my $char = substr(shift,0,1);
935 $char =~ /[\240-\377]/;
936 }
937
51b5cecb 938The above would be adequate if the concern was only with numeric code points.
939However, the concern may be with characters rather than code points
2bbc8d55 940and on an EBCDIC platform it may be desirable for constructs such as
d396a558 941C<if (is_print_ascii("A")) {print "A is a printable character\n";}> to print
942out the expected message. One way to represent the above collection
943of character classification subs that is capable of working across the
944four coded character sets discussed in this document is as follows:
945
946 sub Is_c0 {
947 my $char = substr(shift,0,1);
84f709e7 948 if (ord('^')==94) { # ascii
d396a558 949 return $char =~ /[\000-\037]/;
84f709e7 950 }
951 if (ord('^')==176) { # 37
d396a558 952 return $char =~ /[\000-\003\067\055-\057\026\005\045\013-\023\074\075\062\046\030\031\077\047\034-\037]/;
953 }
84f709e7 954 if (ord('^')==95 || ord('^')==106) { # 1047 || posix-bc
d396a558 955 return $char =~ /[\000-\003\067\055-\057\026\005\025\013-\023\074\075\062\046\030\031\077\047\034-\037]/;
956 }
957 }
958
959 sub Is_print_ascii {
960 my $char = substr(shift,0,1);
961 $char =~ /[ !"\#\$%&'()*+,\-.\/0-9:;<=>?\@A-Z[\\\]^_`a-z{|}~]/;
962 }
963
964 sub Is_delete {
965 my $char = substr(shift,0,1);
84f709e7 966 if (ord('^')==94) { # ascii
d396a558 967 return $char eq "\177";
84f709e7 968 }
969 else { # ebcdic
d396a558 970 return $char eq "\007";
971 }
972 }
973
974 sub Is_c1 {
975 my $char = substr(shift,0,1);
84f709e7 976 if (ord('^')==94) { # ascii
d396a558 977 return $char =~ /[\200-\237]/;
978 }
84f709e7 979 if (ord('^')==176) { # 37
d396a558 980 return $char =~ /[\040-\044\025\006\027\050-\054\011\012\033\060\061\032\063-\066\010\070-\073\040\024\076\377]/;
981 }
84f709e7 982 if (ord('^')==95) { # 1047
d396a558 983 return $char =~ /[\040-\045\006\027\050-\054\011\012\033\060\061\032\063-\066\010\070-\073\040\024\076\377]/;
984 }
84f709e7 985 if (ord('^')==106) { # posix-bc
986 return $char =~
d396a558 987 /[\040-\045\006\027\050-\054\011\012\033\060\061\032\063-\066\010\070-\073\040\024\076\137]/;
988 }
989 }
990
991 sub Is_latin_1 {
992 my $char = substr(shift,0,1);
84f709e7 993 if (ord('^')==94) { # ascii
d396a558 994 return $char =~ /[\240-\377]/;
995 }
84f709e7 996 if (ord('^')==176) { # 37
997 return $char =~
d396a558 998 /[\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]/;
999 }
84f709e7 1000 if (ord('^')==95) { # 1047
d396a558 1001 return $char =~
1002 /[\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]/;
1003 }
84f709e7 1004 if (ord('^')==106) { # posix-bc
1005 return $char =~
d396a558 1006 /[\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]/;
1007 }
1008 }
1009
1010Note however that only the C<Is_ascii_print()> sub is really independent
1011of coded character set. Another way to write C<Is_latin_1()> would be
1012to use the characters in the range explicitly:
1013
1014 sub Is_latin_1 {
1015 my $char = substr(shift,0,1);
aadc0e04 1016 $char =~ /[ ¡¢£¤¥¦§¨©ª«¬\ad®¯°±²³´µ¶·¸¹º»¼½¾¿ÀÁÂÃÄÅÆÇÈÉÊËÌÍÎÏÐÑÒÓÔÕÖ×ØÙÚÛÜÝÞßàáâãäåæçèéêëìíîïðñòóôõö÷øùúûüýþÿ]/;
d396a558 1017 }
1018
1019Although that form may run into trouble in network transit (due to the
1020presence of 8 bit characters) or on non ISO-Latin character sets.
d396a558 1021
1022=head1 SOCKETS
1023
1024Most socket programming assumes ASCII character encodings in network
1025byte order. Exceptions can include CGI script writing under a
1026host web server where the server may take care of translation for you.
1027Most host web servers convert EBCDIC data to ISO-8859-1 or Unicode on
1028output.
1029
1030=head1 SORTING
1031
1032One big difference between ASCII based character sets and EBCDIC ones
1033are the relative positions of upper and lower case letters and the
2bbc8d55 1034letters compared to the digits. If sorted on an ASCII based platform the
d396a558 1035two letter abbreviation for a physician comes before the two letter
1036for drive, that is:
1037
84f709e7 1038 @sorted = sort(qw(Dr. dr.)); # @sorted holds ('Dr.','dr.') on ASCII,
1039 # but ('dr.','Dr.') on EBCDIC
d396a558 1040
1041The property of lower case before uppercase letters in EBCDIC is
1042even carried to the Latin 1 EBCDIC pages such as 0037 and 1047.
b3b6085d 1043An example would be that E<Euml> C<E WITH DIAERESIS> (203) comes
2bbc8d55 1044before E<euml> C<e WITH DIAERESIS> (235) on an ASCII platform, but
1045the latter (83) comes before the former (115) on an EBCDIC platform.
b3b6085d 1046(Astute readers will note that the upper case version of E<szlig>
51b5cecb 1047C<SMALL LETTER SHARP S> is simply "SS" and that the upper case version of
b3b6085d 1048E<yuml> C<y WITH DIAERESIS> is not in the 0..255 range but it is
51b5cecb 1049at U+x0178 in Unicode, or C<"\x{178}"> in a Unicode enabled Perl).
d396a558 1050
1051The sort order will cause differences between results obtained on
2bbc8d55 1052ASCII platforms versus EBCDIC platforms. What follows are some suggestions
d396a558 1053on how to deal with these differences.
1054
51b5cecb 1055=head2 Ignore ASCII vs. EBCDIC sort differences.
d396a558 1056
1057This is the least computationally expensive strategy. It may require
1058some user education.
1059
51b5cecb 1060=head2 MONO CASE then sort data.
d396a558 1061
51b5cecb 1062In order to minimize the expense of mono casing mixed test try to
d396a558 1063C<tr///> towards the character set case most employed within the data.
1064If the data are primarily UPPERCASE non Latin 1 then apply tr/[a-z]/[A-Z]/
1065then sort(). If the data are primarily lowercase non Latin 1 then
1066apply tr/[A-Z]/[a-z]/ before sorting. If the data are primarily UPPERCASE
51b5cecb 1067and include Latin-1 characters then apply:
1068
0be03469 1069 tr/[a-z]/[A-Z]/;
aadc0e04 1070 tr/[àáâãäåæçèéêëìíîïðñòóôõöøùúûüýþ]/[ÀÁÂÃÄÅÆÇÈÉÊËÌÍÎÏÐÑÒÓÔÕÖØÙÚÛÜÝÞ/;
0be03469 1071 s/ß/SS/g;
d396a558 1072
51b5cecb 1073then sort(). Do note however that such Latin-1 manipulation does not
b3b6085d 1074address the E<yuml> C<y WITH DIAERESIS> character that will remain at
2bbc8d55 1075code point 255 on ASCII platforms, but 223 on most EBCDIC platforms
51b5cecb 1076where it will sort to a place less than the EBCDIC numerals. With a
1077Unicode enabled Perl you might try:
d396a558 1078
51b5cecb 1079 tr/^?/\x{178}/;
1080
1081The strategy of mono casing data before sorting does not preserve the case
1082of the data and may not be acceptable for that reason.
1083
1084=head2 Convert, sort data, then re convert.
d396a558 1085
1086This is the most expensive proposition that does not employ a network
1087connection.
1088
2bbc8d55 1089=head2 Perform sorting on one type of platform only.
d396a558 1090
1091This strategy can employ a network connection. As such
1092it would be computationally expensive.
1093
395f5a0c 1094=head1 TRANSFORMATION FORMATS
1e054b24 1095
1096There are a variety of ways of transforming data with an intra character set
1097mapping that serve a variety of purposes. Sorting was discussed in the
1098previous section and a few of the other more popular mapping techniques are
1099discussed next.
1100
1101=head2 URL decoding and encoding
d396a558 1102
51b5cecb 1103Note that some URLs have hexadecimal ASCII code points in them in an
1e054b24 1104attempt to overcome character or protocol limitation issues. For example
1105the tilde character is not on every keyboard hence a URL of the form:
d396a558 1106
1107 http://www.pvhp.com/~pvhp/
1108
1109may also be expressed as either of:
1110
1111 http://www.pvhp.com/%7Epvhp/
1112
1113 http://www.pvhp.com/%7epvhp/
1114
51b5cecb 1115where 7E is the hexadecimal ASCII code point for '~'. Here is an example
d396a558 1116of decoding such a URL under CCSID 1047:
1117
84f709e7 1118 $url = 'http://www.pvhp.com/%7Epvhp/';
d396a558 1119 # this array assumes code page 1047
1120 my @a2e_1047 = (
1121 0, 1, 2, 3, 55, 45, 46, 47, 22, 5, 21, 11, 12, 13, 14, 15,
1122 16, 17, 18, 19, 60, 61, 50, 38, 24, 25, 63, 39, 28, 29, 30, 31,
1123 64, 90,127,123, 91,108, 80,125, 77, 93, 92, 78,107, 96, 75, 97,
1124 240,241,242,243,244,245,246,247,248,249,122, 94, 76,126,110,111,
1125 124,193,194,195,196,197,198,199,200,201,209,210,211,212,213,214,
1126 215,216,217,226,227,228,229,230,231,232,233,173,224,189, 95,109,
1127 121,129,130,131,132,133,134,135,136,137,145,146,147,148,149,150,
1128 151,152,153,162,163,164,165,166,167,168,169,192, 79,208,161, 7,
1129 32, 33, 34, 35, 36, 37, 6, 23, 40, 41, 42, 43, 44, 9, 10, 27,
1130 48, 49, 26, 51, 52, 53, 54, 8, 56, 57, 58, 59, 4, 20, 62,255,
1131 65,170, 74,177,159,178,106,181,187,180,154,138,176,202,175,188,
1132 144,143,234,250,190,160,182,179,157,218,155,139,183,184,185,171,
1133 100,101, 98,102, 99,103,158,104,116,113,114,115,120,117,118,119,
1134 172,105,237,238,235,239,236,191,128,253,254,251,252,186,174, 89,
1135 68, 69, 66, 70, 67, 71,156, 72, 84, 81, 82, 83, 88, 85, 86, 87,
1136 140, 73,205,206,203,207,204,225,112,221,222,219,220,141,142,223
1137 );
1138 $url =~ s/%([0-9a-fA-F]{2})/pack("c",$a2e_1047[hex($1)])/ge;
1139
1e054b24 1140Conversely, here is a partial solution for the task of encoding such
1141a URL under the 1047 code page:
1142
84f709e7 1143 $url = 'http://www.pvhp.com/~pvhp/';
1e054b24 1144 # this array assumes code page 1047
1145 my @e2a_1047 = (
1146 0, 1, 2, 3,156, 9,134,127,151,141,142, 11, 12, 13, 14, 15,
1147 16, 17, 18, 19,157, 10, 8,135, 24, 25,146,143, 28, 29, 30, 31,
1148 128,129,130,131,132,133, 23, 27,136,137,138,139,140, 5, 6, 7,
1149 144,145, 22,147,148,149,150, 4,152,153,154,155, 20, 21,158, 26,
1150 32,160,226,228,224,225,227,229,231,241,162, 46, 60, 40, 43,124,
1151 38,233,234,235,232,237,238,239,236,223, 33, 36, 42, 41, 59, 94,
1152 45, 47,194,196,192,193,195,197,199,209,166, 44, 37, 95, 62, 63,
1153 248,201,202,203,200,205,206,207,204, 96, 58, 35, 64, 39, 61, 34,
1154 216, 97, 98, 99,100,101,102,103,104,105,171,187,240,253,254,177,
1155 176,106,107,108,109,110,111,112,113,114,170,186,230,184,198,164,
1156 181,126,115,116,117,118,119,120,121,122,161,191,208, 91,222,174,
1157 172,163,165,183,169,167,182,188,189,190,221,168,175, 93,180,215,
1158 123, 65, 66, 67, 68, 69, 70, 71, 72, 73,173,244,246,242,243,245,
1159 125, 74, 75, 76, 77, 78, 79, 80, 81, 82,185,251,252,249,250,255,
1160 92,247, 83, 84, 85, 86, 87, 88, 89, 90,178,212,214,210,211,213,
1161 48, 49, 50, 51, 52, 53, 54, 55, 56, 57,179,219,220,217,218,159
1162 );
84f709e7 1163 # The following regular expression does not address the
1e054b24 1164 # mappings for: ('.' => '%2E', '/' => '%2F', ':' => '%3A')
1165 $url =~ s/([\t "#%&\(\),;<=>\?\@\[\\\]^`{|}~])/sprintf("%%%02X",$e2a_1047[ord($1)])/ge;
1166
1167where a more complete solution would split the URL into components
1168and apply a full s/// substitution only to the appropriate parts.
1169
1170In the remaining examples a @e2a or @a2e array may be employed
1171but the assignment will not be shown explicitly. For code page 1047
1172you could use the @a2e_1047 or @e2a_1047 arrays just shown.
1173
1174=head2 uu encoding and decoding
1175
1176The C<u> template to pack() or unpack() will render EBCDIC data in EBCDIC
1177characters equivalent to their ASCII counterparts. For example, the
1178following will print "Yes indeed\n" on either an ASCII or EBCDIC computer:
1179
84f709e7 1180 $all_byte_chrs = '';
1181 for (0..255) { $all_byte_chrs .= chr($_); }
1182 $uuencode_byte_chrs = pack('u', $all_byte_chrs);
210b36aa 1183 ($uu = <<'ENDOFHEREDOC') =~ s/^\s*//gm;
1e054b24 1184 M``$"`P0%!@<("0H+#`T.#Q`1$A,4%187&!D:&QP='A\@(2(C)"4F)R@I*BLL
1185 M+2XO,#$R,S0U-C<X.3H[/#T^/T!!0D-$149'2$E*2TQ-3D]045)35%565UA9
1186 M6EM<75Y?8&%B8V1E9F=H:6IK;&UN;W!Q<G-T=79W>'EZ>WQ]?G^`@8*#A(6&
1187 MAXB)BHN,C8Z/D)&2DY25EI>8F9J;G)V>GZ"AHJ.DI::GJ*FJJZRMKJ^PL;*S
1188 MM+6VM[BYNKN\O;Z_P,'"P\3%QL?(R<K+S,W.S]#1TM/4U=;7V-G:V]S=WM_@
1189 ?X>+CY.7FY^CIZNOL[>[O\/'R\_3U]O?X^?K[_/W^_P``
1190 ENDOFHEREDOC
84f709e7 1191 if ($uuencode_byte_chrs eq $uu) {
1e054b24 1192 print "Yes ";
1193 }
1194 $uudecode_byte_chrs = unpack('u', $uuencode_byte_chrs);
84f709e7 1195 if ($uudecode_byte_chrs eq $all_byte_chrs) {
1e054b24 1196 print "indeed\n";
1197 }
1198
1199Here is a very spartan uudecoder that will work on EBCDIC provided
1200that the @e2a array is filled in appropriately:
1201
84f709e7 1202 #!/usr/local/bin/perl
1203 @e2a = ( # this must be filled in
1204 );
1205 $_ = <> until ($mode,$file) = /^begin\s*(\d*)\s*(\S*)/;
1e054b24 1206 open(OUT, "> $file") if $file ne "";
1207 while(<>) {
1208 last if /^end/;
1209 next if /[a-z]/;
1210 next unless int(((($e2a[ord()] - 32 ) & 077) + 2) / 3) ==
1211 int(length() / 4);
1212 print OUT unpack("u", $_);
1213 }
1214 close(OUT);
1215 chmod oct($mode), $file;
1216
1217
1218=head2 Quoted-Printable encoding and decoding
1219
2bbc8d55 1220On ASCII encoded platforms it is possible to strip characters outside of
1e054b24 1221the printable set using:
1222
1223 # This QP encoder works on ASCII only
84f709e7 1224 $qp_string =~ s/([=\x00-\x1F\x80-\xFF])/sprintf("=%02X",ord($1))/ge;
1e054b24 1225
2bbc8d55 1226Whereas a QP encoder that works on both ASCII and EBCDIC platforms
1e054b24 1227would look somewhat like the following (where the EBCDIC branch @e2a
1228array is omitted for brevity):
1229
1230 if (ord('A') == 65) { # ASCII
1231 $delete = "\x7F"; # ASCII
1232 @e2a = (0 .. 255) # ASCII to ASCII identity map
84f709e7 1233 }
1234 else { # EBCDIC
1e054b24 1235 $delete = "\x07"; # EBCDIC
84f709e7 1236 @e2a = # EBCDIC to ASCII map (as shown above)
1e054b24 1237 }
84f709e7 1238 $qp_string =~
1e054b24 1239 s/([^ !"\#\$%&'()*+,\-.\/0-9:;<>?\@A-Z[\\\]^_`a-z{|}~$delete])/sprintf("=%02X",$e2a[ord($1)])/ge;
1240
1241(although in production code the substitutions might be done
1242in the EBCDIC branch with the @e2a array and separately in the
1243ASCII branch without the expense of the identity map).
1244
1245Such QP strings can be decoded with:
1246
1247 # This QP decoder is limited to ASCII only
1248 $string =~ s/=([0-9A-Fa-f][0-9A-Fa-f])/chr hex $1/ge;
1249 $string =~ s/=[\n\r]+$//;
1250
2bbc8d55 1251Whereas a QP decoder that works on both ASCII and EBCDIC platforms
1e054b24 1252would look somewhat like the following (where the @a2e array is
1253omitted for brevity):
1254
1255 $string =~ s/=([0-9A-Fa-f][0-9A-Fa-f])/chr $a2e[hex $1]/ge;
1256 $string =~ s/=[\n\r]+$//;
1257
395f5a0c 1258=head2 Caesarian ciphers
1e054b24 1259
1260The practice of shifting an alphabet one or more characters for encipherment
1261dates back thousands of years and was explicitly detailed by Gaius Julius
1262Caesar in his B<Gallic Wars> text. A single alphabet shift is sometimes
1263referred to as a rotation and the shift amount is given as a number $n after
1264the string 'rot' or "rot$n". Rot0 and rot26 would designate identity maps
1265on the 26 letter English version of the Latin alphabet. Rot13 has the
1266interesting property that alternate subsequent invocations are identity maps
1267(thus rot13 is its own non-trivial inverse in the group of 26 alphabet
1268rotations). Hence the following is a rot13 encoder and decoder that will
2bbc8d55 1269work on ASCII and EBCDIC platforms:
1e054b24 1270
1271 #!/usr/local/bin/perl
1272
84f709e7 1273 while(<>){
1e054b24 1274 tr/n-za-mN-ZA-M/a-zA-Z/;
1275 print;
1276 }
1277
1278In one-liner form:
1279
84f709e7 1280 perl -ne 'tr/n-za-mN-ZA-M/a-zA-Z/;print'
1e054b24 1281
1282
1283=head1 Hashing order and checksums
1284
395f5a0c 1285To the extent that it is possible to write code that depends on
1286hashing order there may be differences between hashes as stored
2bbc8d55 1287on an ASCII based platform and hashes stored on an EBCDIC based platform.
1e054b24 1288XXX
1289
d396a558 1290=head1 I18N AND L10N
1291
1292Internationalization(I18N) and localization(L10N) are supported at least
2bbc8d55 1293in principle even on EBCDIC platforms. The details are system dependent
d396a558 1294and discussed under the L<perlebcdic/OS ISSUES> section below.
1295
1296=head1 MULTI OCTET CHARACTER SETS
1297
395f5a0c 1298Perl may work with an internal UTF-EBCDIC encoding form for wide characters
1299on EBCDIC platforms in a manner analogous to the way that it works with
1300the UTF-8 internal encoding form on ASCII based platforms.
1301
1302Legacy multi byte EBCDIC code pages XXX.
d396a558 1303
1304=head1 OS ISSUES
1305
1306There may be a few system dependent issues
1307of concern to EBCDIC Perl programmers.
1308
522b859a 1309=head2 OS/400
51b5cecb 1310
d396a558 1311=over 8
1312
522b859a 1313=item PASE
1314
1315The PASE environment is runtime environment for OS/400 that can run
1316executables built for PowerPC AIX in OS/400, see L<perlos400>. PASE
1317is ASCII-based, not EBCDIC-based as the ILE.
1318
d396a558 1319=item IFS access
1320
1321XXX.
1322
1323=back
1324
395f5a0c 1325=head2 OS/390, z/OS
d396a558 1326
51b5cecb 1327Perl runs under Unix Systems Services or USS.
1328
d396a558 1329=over 8
1330
51b5cecb 1331=item chcp
1332
1e054b24 1333B<chcp> is supported as a shell utility for displaying and changing
1334one's code page. See also L<chcp>.
51b5cecb 1335
d396a558 1336=item dataset access
1337
1338For sequential data set access try:
1339
1340 my @ds_records = `cat //DSNAME`;
1341
1342or:
1343
1344 my @ds_records = `cat //'HLQ.DSNAME'`;
1345
1346See also the OS390::Stdio module on CPAN.
1347
395f5a0c 1348=item OS/390, z/OS iconv
51b5cecb 1349
1e054b24 1350B<iconv> is supported as both a shell utility and a C RTL routine.
1351See also the iconv(1) and iconv(3) manual pages.
51b5cecb 1352
d396a558 1353=item locales
1354
395f5a0c 1355On OS/390 or z/OS see L<locale> for information on locales. The L10N files
1356are in F</usr/nls/locale>. $Config{d_setlocale} is 'define' on OS/390
1357or z/OS.
d396a558 1358
1359=back
1360
1361=head2 VM/ESA?
1362
1363XXX.
1364
1365=head2 POSIX-BC?
1366
1367XXX.
1368
51b5cecb 1369=head1 BUGS
1370
1371This pod document contains literal Latin 1 characters and may encounter
b1866b2d 1372translation difficulties. In particular one popular nroff implementation
51b5cecb 1373was known to strip accented characters to their unaccented counterparts
1374while attempting to view this document through the B<pod2man> program
1375(for example, you may see a plain C<y> rather than one with a diaeresis
3958b146 1376as in E<yuml>). Another nroff truncated the resultant manpage at
395f5a0c 1377the first occurrence of 8 bit characters.
51b5cecb 1378
1379Not all shells will allow multiple C<-e> string arguments to perl to
395f5a0c 1380be concatenated together properly as recipes 0, 2, 4, 5, and 6 might
1381seem to imply.
51b5cecb 1382
b3b6085d 1383=head1 SEE ALSO
1384
395f5a0c 1385L<perllocale>, L<perlfunc>, L<perlunicode>, L<utf8>.
b3b6085d 1386
d396a558 1387=head1 REFERENCES
1388
2bbc8d55 1389L<http://anubis.dkuug.dk/i18n/charmaps>
d396a558 1390
2bbc8d55 1391L<http://www.unicode.org/>
d396a558 1392
2bbc8d55 1393L<http://www.unicode.org/unicode/reports/tr16/>
d396a558 1394
08d7a6b2 1395L<http://www.wps.com/projects/codes/>
51b5cecb 1396B<ASCII: American Standard Code for Information Infiltration> Tom Jennings,
1397September 1999.
1398
395f5a0c 1399B<The Unicode Standard, Version 3.0> The Unicode Consortium, Lisa Moore ed.,
51b5cecb 1400ISBN 0-201-61633-5, Addison Wesley Developers Press, February 2000.
1401
d396a558 1402B<CDRA: IBM - Character Data Representation Architecture -
1403Reference and Registry>, IBM SC09-2190-00, December 1996.
1404
1405"Demystifying Character Sets", Andrea Vine, Multilingual Computing
1406& Technology, B<#26 Vol. 10 Issue 4>, August/September 1999;
1407ISSN 1523-0309; Multilingual Computing Inc. Sandpoint ID, USA.
1408
1e054b24 1409B<Codes, Ciphers, and Other Cryptic and Clandestine Communication>
1410Fred B. Wrixon, ISBN 1-57912-040-7, Black Dog & Leventhal Publishers,
14111998.
1412
2bbc8d55 1413L<http://www.bobbemer.com/P-BIT.HTM>
395f5a0c 1414B<IBM - EBCDIC and the P-bit; The biggest Computer Goof Ever> Robert Bemer.
1415
1416=head1 HISTORY
1417
141815 April 2001: added UTF-8 and UTF-EBCDIC to main table, pvhp.
1419
d396a558 1420=head1 AUTHOR
1421
b3b6085d 1422Peter Prymmer pvhp@best.com wrote this in 1999 and 2000
d396a558 1423with CCSID 0819 and 0037 help from Chris Leach and
b3b6085d 1424AndrE<eacute> Pirard A.Pirard@ulg.ac.be as well as POSIX-BC
1425help from Thomas Dorner Thomas.Dorner@start.de.
1e054b24 1426Thanks also to Vickie Cooper, Philip Newton, William Raffloer, and
1427Joe Smith. Trademarks, registered trademarks, service marks and
1428registered service marks used in this document are the property of
1429their respective owners.
84f709e7 1430
1431
Unnamed repository; edit this file to name it for gitweb.