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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
14=head1 COMMON CHARACTER CODE SETS
15
16=head2 ASCII
17
2bbc8d55 18The American Standard Code for Information Interchange (ASCII or US-ASCII) is a
19set of
d396a558 20integers running from 0 to 127 (decimal) that imply character
2bbc8d55 21interpretation by the display and other systems of computers.
51b5cecb 22The range 0..127 can be covered by setting the bits in a 7-bit binary
d396a558 23digit, hence the set is sometimes referred to as a "7-bit ASCII".
51b5cecb 24ASCII was described by the American National Standards Institute
d396a558 25document ANSI X3.4-1986. It was also described by ISO 646:1991
26(with localization for currency symbols). The full ASCII set is
27given in the table below as the first 128 elements. Languages that
28can be written adequately with the characters in ASCII include
29English, Hawaiian, Indonesian, Swahili and some Native American
30languages.
31
51b5cecb 32There are many character sets that extend the range of integers
33from 0..2**7-1 up to 2**8-1, or 8 bit bytes (octets if you prefer).
34One common one is the ISO 8859-1 character set.
35
d396a558 36=head2 ISO 8859
37
38The ISO 8859-$n are a collection of character code sets from the
39International Organization for Standardization (ISO) each of which
40adds characters to the ASCII set that are typically found in European
41languages many of which are based on the Roman, or Latin, alphabet.
42
43=head2 Latin 1 (ISO 8859-1)
44
45A particular 8-bit extension to ASCII that includes grave and acute
46accented Latin characters. Languages that can employ ISO 8859-1
47include all the languages covered by ASCII as well as Afrikaans,
48Albanian, Basque, Catalan, Danish, Faroese, Finnish, Norwegian,
3958b146 49Portuguese, Spanish, and Swedish. Dutch is covered albeit without
d396a558 50the ij ligature. French is covered too but without the oe ligature.
51German can use ISO 8859-1 but must do so without German-style
52quotation marks. This set is based on Western European extensions
53to ASCII and is commonly encountered in world wide web work.
54In IBM character code set identification terminology ISO 8859-1 is
51b5cecb 55also known as CCSID 819 (or sometimes 0819 or even 00819).
d396a558 56
57=head2 EBCDIC
58
395f5a0c 59The Extended Binary Coded Decimal Interchange Code refers to a
51b5cecb 60large collection of slightly different single and multi byte
61coded character sets that are different from ASCII or ISO 8859-1
62and typically run on host computers. The EBCDIC encodings derive
63from 8 bit byte extensions of Hollerith punched card encodings.
d396a558 64The layout on the cards was such that high bits were set for the
65upper and lower case alphabet characters [a-z] and [A-Z], but there
6c981e14 66were gaps within each Latin alphabet range.
d396a558 67
51b5cecb 68Some IBM EBCDIC character sets may be known by character code set
69identification numbers (CCSID numbers) or code page numbers. Leading
70zero digits in CCSID numbers within this document are insignificant.
71E.g. CCSID 0037 may be referred to as 37 in places.
72
2bbc8d55 73Perl can be compiled on platforms that run any of three commonly used EBCDIC
74character sets, listed below.
75
f4084e39 76=head2 The 13 variant characters
1e054b24 77
51b5cecb 78Among IBM EBCDIC character code sets there are 13 characters that
79are often mapped to different integer values. Those characters
80are known as the 13 "variant" characters and are:
d396a558 81
51b5cecb 82 \ [ ] { } ^ ~ ! # | $ @ `
d396a558 83
2bbc8d55 84When Perl is compiled for a platform, it looks at some of these characters to
85guess which EBCDIC character set the platform uses, and adapts itself
86accordingly to that platform. If the platform uses a character set that is not
87one of the three Perl knows about, Perl will either fail to compile, or
88mistakenly and silently choose one of the three.
89They are:
90
d396a558 91=head2 0037
92
93Character code set ID 0037 is a mapping of the ASCII plus Latin-1
94characters (i.e. ISO 8859-1) to an EBCDIC set. 0037 is used
51b5cecb 95in North American English locales on the OS/400 operating system
96that runs on AS/400 computers. CCSID 37 differs from ISO 8859-1
97in 237 places, in other words they agree on only 19 code point values.
d396a558 98
99=head2 1047
100
101Character code set ID 1047 is also a mapping of the ASCII plus
102Latin-1 characters (i.e. ISO 8859-1) to an EBCDIC set. 1047 is
395f5a0c 103used under Unix System Services for OS/390 or z/OS, and OpenEdition
104for VM/ESA. CCSID 1047 differs from CCSID 0037 in eight places.
d396a558 105
106=head2 POSIX-BC
107
108The EBCDIC code page in use on Siemens' BS2000 system is distinct from
1091047 and 0037. It is identified below as the POSIX-BC set.
110
64c66fb6 111=head2 Unicode code points versus EBCDIC code points
112
113In Unicode terminology a I<code point> is the number assigned to a
114character: for example, in EBCDIC the character "A" is usually assigned
115the number 193. In Unicode the character "A" is assigned the number 65.
116This causes a problem with the semantics of the pack/unpack "U", which
117are supposed to pack Unicode code points to characters and back to numbers.
118The problem is: which code points to use for code points less than 256?
119(for 256 and over there's no problem: Unicode code points are used)
120In EBCDIC, for the low 256 the EBCDIC code points are used. This
121means that the equivalences
122
123 pack("U", ord($character)) eq $character
124 unpack("U", $character) == ord $character
125
126will hold. (If Unicode code points were applied consistently over
127all the possible code points, pack("U",ord("A")) would in EBCDIC
128equal I<A with acute> or chr(101), and unpack("U", "A") would equal
12965, or I<non-breaking space>, not 193, or ord "A".)
130
dc4af4bb 131=head2 Remaining Perl Unicode problems in EBCDIC
132
133=over 4
134
135=item *
136
2bbc8d55 137Many of the remaining problems seem to be related to case-insensitive matching
dc4af4bb 138
139=item *
140
141The extensions Unicode::Collate and Unicode::Normalized are not
142supported under EBCDIC, likewise for the encoding pragma.
143
144=back
145
395f5a0c 146=head2 Unicode and UTF
147
2bbc8d55 148UTF stands for C<Unicode Transformation Format>.
149UTF-8 is an encoding of Unicode into a sequence of 8-bit byte chunks, based on
150ASCII and Latin-1.
151The length of a sequence required to represent a Unicode code point
152depends on the ordinal number of that code point,
153with larger numbers requiring more bytes.
154UTF-EBCDIC is like UTF-8, but based on EBCDIC.
155
fe749c9a 156You may see the term C<invariant> character or code point.
157This simply means that the character has the same numeric
158value when encoded as when not.
42bde815 159(Note that this is a very different concept from L</The 13 variant characters>
2bbc8d55 160mentioned above.)
fe749c9a 161For example, the ordinal value of 'A' is 193 in most EBCDIC code pages,
162and also is 193 when encoded in UTF-EBCDIC.
163All other code points occupy at least two bytes when encoded.
164In UTF-8, the code points corresponding to the lowest 128
165ordinal numbers (0 - 127: the ASCII characters) are invariant.
166In UTF-EBCDIC, there are 160 invariant characters.
2bbc8d55 167(If you care, the EBCDIC invariants are those characters
fe749c9a 168which have ASCII equivalents, plus those that correspond to
2bbc8d55 169the C1 controls (80..9f on ASCII platforms).)
fe749c9a 170
2bbc8d55 171A string encoded in UTF-EBCDIC may be longer (but never shorter) than
172one encoded in UTF-8.
395f5a0c 173
8704cfd1 174=head2 Using Encode
8f94de01 175
176Starting from Perl 5.8 you can use the standard new module Encode
2bbc8d55 177to translate from EBCDIC to Latin-1 code points.
178Encode knows about more EBCDIC character sets than Perl can currently
179be compiled to run on.
8f94de01 180
181 use Encode 'from_to';
182
183 my %ebcdic = ( 176 => 'cp37', 95 => 'cp1047', 106 => 'posix-bc' );
184
185 # $a is in EBCDIC code points
186 from_to($a, $ebcdic{ord '^'}, 'latin1');
187 # $a is ISO 8859-1 code points
188
189and from Latin-1 code points to EBCDIC code points
190
191 use Encode 'from_to';
192
193 my %ebcdic = ( 176 => 'cp37', 95 => 'cp1047', 106 => 'posix-bc' );
194
195 # $a is ISO 8859-1 code points
196 from_to($a, 'latin1', $ebcdic{ord '^'});
197 # $a is in EBCDIC code points
198
199For doing I/O it is suggested that you use the autotranslating features
200of PerlIO, see L<perluniintro>.
201
aa2b82fc 202Since version 5.8 Perl uses the new PerlIO I/O library. This enables
203you to use different encodings per IO channel. For example you may use
204
205 use Encode;
206 open($f, ">:encoding(ascii)", "test.ascii");
207 print $f "Hello World!\n";
208 open($f, ">:encoding(cp37)", "test.ebcdic");
209 print $f "Hello World!\n";
210 open($f, ">:encoding(latin1)", "test.latin1");
211 print $f "Hello World!\n";
212 open($f, ">:encoding(utf8)", "test.utf8");
213 print $f "Hello World!\n";
214
2bbc8d55 215to get four files containing "Hello World!\n" in ASCII, CP 37 EBCDIC,
216ISO 8859-1 (Latin-1) (in this example identical to ASCII since only ASCII
217characters were printed), and
218UTF-EBCDIC (in this example identical to normal EBCDIC since only characters
219that don't differ between EBCDIC and UTF-EBCDIC were printed). See the
aa2b82fc 220documentation of Encode::PerlIO for details.
221
222As the PerlIO layer uses raw IO (bytes) internally, all this totally
223ignores things like the type of your filesystem (ASCII or EBCDIC).
224
d396a558 225=head1 SINGLE OCTET TABLES
226
227The following tables list the ASCII and Latin 1 ordered sets including
228the subsets: C0 controls (0..31), ASCII graphics (32..7e), delete (7f),
229C1 controls (80..9f), and Latin-1 (a.k.a. ISO 8859-1) (a0..ff). In the
230table non-printing control character names as well as the Latin 1
231extensions to ASCII have been labelled with character names roughly
395f5a0c 232corresponding to I<The Unicode Standard, Version 3.0> albeit with
d396a558 233substitutions such as s/LATIN// and s/VULGAR// in all cases,
234s/CAPITAL LETTER// in some cases, and s/SMALL LETTER ([A-Z])/\l$1/
1e054b24 235in some other cases (the C<charnames> pragma names unfortunately do
236not list explicit names for the C0 or C1 control characters). The
237"names" of the C1 control set (128..159 in ISO 8859-1) listed here are
238somewhat arbitrary. The differences between the 0037 and 1047 sets are
239flagged with ***. The differences between the 1047 and POSIX-BC sets
240are flagged with ###. All ord() numbers listed are decimal. If you
241would rather see this table listing octal values then run the table
242(that is, the pod version of this document since this recipe may not
243work with a pod2_other_format translation) through:
d396a558 244
245=over 4
246
247=item recipe 0
248
249=back
250
84f709e7 251 perl -ne 'if(/(.{33})(\d+)\s+(\d+)\s+(\d+)\s+(\d+)/)' \
252 -e '{printf("%s%-9o%-9o%-9o%o\n",$1,$2,$3,$4,$5)}' perlebcdic.pod
395f5a0c 253
254If you want to retain the UTF-x code points then in script form you
255might want to write:
256
257=over 4
258
259=item recipe 1
260
261=back
262
84f709e7 263 open(FH,"<perlebcdic.pod") or die "Could not open perlebcdic.pod: $!";
264 while (<FH>) {
265 if (/(.{33})(\d+)\s+(\d+)\s+(\d+)\s+(\d+)\s+(\d+)\.?(\d*)\s+(\d+)\.?(\d*)/) {
266 if ($7 ne '' && $9 ne '') {
267 printf("%s%-9o%-9o%-9o%-9o%-3o.%-5o%-3o.%o\n",$1,$2,$3,$4,$5,$6,$7,$8,$9);
268 }
269 elsif ($7 ne '') {
270 printf("%s%-9o%-9o%-9o%-9o%-3o.%-5o%o\n",$1,$2,$3,$4,$5,$6,$7,$8);
271 }
272 else {
273 printf("%s%-9o%-9o%-9o%-9o%-9o%o\n",$1,$2,$3,$4,$5,$6,$8);
395f5a0c 274 }
275 }
276 }
d396a558 277
278If you would rather see this table listing hexadecimal values then
279run the table through:
280
281=over 4
282
395f5a0c 283=item recipe 2
d396a558 284
285=back
286
84f709e7 287 perl -ne 'if(/(.{33})(\d+)\s+(\d+)\s+(\d+)\s+(\d+)/)' \
288 -e '{printf("%s%-9X%-9X%-9X%X\n",$1,$2,$3,$4,$5)}' perlebcdic.pod
395f5a0c 289
290Or, in order to retain the UTF-x code points in hexadecimal:
291
292=over 4
293
294=item recipe 3
295
296=back
297
84f709e7 298 open(FH,"<perlebcdic.pod") or die "Could not open perlebcdic.pod: $!";
395f5a0c 299 while (<FH>) {
84f709e7 300 if (/(.{33})(\d+)\s+(\d+)\s+(\d+)\s+(\d+)\s+(\d+)\.?(\d*)\s+(\d+)\.?(\d*)/) {
301 if ($7 ne '' && $9 ne '') {
302 printf("%s%-9X%-9X%-9X%-9X%-2X.%-6X%-2X.%X\n",$1,$2,$3,$4,$5,$6,$7,$8,$9);
395f5a0c 303 }
84f709e7 304 elsif ($7 ne '') {
305 printf("%s%-9X%-9X%-9X%-9X%-2X.%-6X%X\n",$1,$2,$3,$4,$5,$6,$7,$8);
395f5a0c 306 }
307 else {
84f709e7 308 printf("%s%-9X%-9X%-9X%-9X%-9X%X\n",$1,$2,$3,$4,$5,$6,$8);
395f5a0c 309 }
310 }
311 }
312
313
314 incomp- incomp-
315 8859-1 lete lete
316 chr 0819 0037 1047 POSIX-BC UTF-8 UTF-EBCDIC
317 ------------------------------------------------------------------------------------
318 <NULL> 0 0 0 0 0 0
319 <START OF HEADING> 1 1 1 1 1 1
320 <START OF TEXT> 2 2 2 2 2 2
321 <END OF TEXT> 3 3 3 3 3 3
322 <END OF TRANSMISSION> 4 55 55 55 4 55
323 <ENQUIRY> 5 45 45 45 5 45
324 <ACKNOWLEDGE> 6 46 46 46 6 46
325 <BELL> 7 47 47 47 7 47
326 <BACKSPACE> 8 22 22 22 8 22
327 <HORIZONTAL TABULATION> 9 5 5 5 9 5
328 <LINE FEED> 10 37 21 21 10 21 ***
329 <VERTICAL TABULATION> 11 11 11 11 11 11
330 <FORM FEED> 12 12 12 12 12 12
331 <CARRIAGE RETURN> 13 13 13 13 13 13
332 <SHIFT OUT> 14 14 14 14 14 14
333 <SHIFT IN> 15 15 15 15 15 15
334 <DATA LINK ESCAPE> 16 16 16 16 16 16
335 <DEVICE CONTROL ONE> 17 17 17 17 17 17
336 <DEVICE CONTROL TWO> 18 18 18 18 18 18
337 <DEVICE CONTROL THREE> 19 19 19 19 19 19
338 <DEVICE CONTROL FOUR> 20 60 60 60 20 60
339 <NEGATIVE ACKNOWLEDGE> 21 61 61 61 21 61
340 <SYNCHRONOUS IDLE> 22 50 50 50 22 50
341 <END OF TRANSMISSION BLOCK> 23 38 38 38 23 38
342 <CANCEL> 24 24 24 24 24 24
343 <END OF MEDIUM> 25 25 25 25 25 25
344 <SUBSTITUTE> 26 63 63 63 26 63
345 <ESCAPE> 27 39 39 39 27 39
346 <FILE SEPARATOR> 28 28 28 28 28 28
347 <GROUP SEPARATOR> 29 29 29 29 29 29
348 <RECORD SEPARATOR> 30 30 30 30 30 30
349 <UNIT SEPARATOR> 31 31 31 31 31 31
350 <SPACE> 32 64 64 64 32 64
351 ! 33 90 90 90 33 90
352 " 34 127 127 127 34 127
353 # 35 123 123 123 35 123
354 $ 36 91 91 91 36 91
355 % 37 108 108 108 37 108
356 & 38 80 80 80 38 80
357 ' 39 125 125 125 39 125
358 ( 40 77 77 77 40 77
359 ) 41 93 93 93 41 93
360 * 42 92 92 92 42 92
361 + 43 78 78 78 43 78
362 , 44 107 107 107 44 107
363 - 45 96 96 96 45 96
364 . 46 75 75 75 46 75
365 / 47 97 97 97 47 97
366 0 48 240 240 240 48 240
367 1 49 241 241 241 49 241
368 2 50 242 242 242 50 242
369 3 51 243 243 243 51 243
370 4 52 244 244 244 52 244
371 5 53 245 245 245 53 245
372 6 54 246 246 246 54 246
373 7 55 247 247 247 55 247
374 8 56 248 248 248 56 248
375 9 57 249 249 249 57 249
376 : 58 122 122 122 58 122
377 ; 59 94 94 94 59 94
378 < 60 76 76 76 60 76
379 = 61 126 126 126 61 126
380 > 62 110 110 110 62 110
381 ? 63 111 111 111 63 111
382 @ 64 124 124 124 64 124
383 A 65 193 193 193 65 193
384 B 66 194 194 194 66 194
385 C 67 195 195 195 67 195
386 D 68 196 196 196 68 196
387 E 69 197 197 197 69 197
388 F 70 198 198 198 70 198
389 G 71 199 199 199 71 199
390 H 72 200 200 200 72 200
391 I 73 201 201 201 73 201
392 J 74 209 209 209 74 209
393 K 75 210 210 210 75 210
394 L 76 211 211 211 76 211
395 M 77 212 212 212 77 212
396 N 78 213 213 213 78 213
397 O 79 214 214 214 79 214
398 P 80 215 215 215 80 215
399 Q 81 216 216 216 81 216
400 R 82 217 217 217 82 217
401 S 83 226 226 226 83 226
402 T 84 227 227 227 84 227
403 U 85 228 228 228 85 228
404 V 86 229 229 229 86 229
405 W 87 230 230 230 87 230
406 X 88 231 231 231 88 231
407 Y 89 232 232 232 89 232
408 Z 90 233 233 233 90 233
409 [ 91 186 173 187 91 173 *** ###
410 \ 92 224 224 188 92 224 ###
411 ] 93 187 189 189 93 189 ***
412 ^ 94 176 95 106 94 95 *** ###
413 _ 95 109 109 109 95 109
414 ` 96 121 121 74 96 121 ###
415 a 97 129 129 129 97 129
416 b 98 130 130 130 98 130
417 c 99 131 131 131 99 131
418 d 100 132 132 132 100 132
419 e 101 133 133 133 101 133
420 f 102 134 134 134 102 134
421 g 103 135 135 135 103 135
422 h 104 136 136 136 104 136
423 i 105 137 137 137 105 137
424 j 106 145 145 145 106 145
425 k 107 146 146 146 107 146
426 l 108 147 147 147 108 147
427 m 109 148 148 148 109 148
428 n 110 149 149 149 110 149
429 o 111 150 150 150 111 150
430 p 112 151 151 151 112 151
431 q 113 152 152 152 113 152
432 r 114 153 153 153 114 153
433 s 115 162 162 162 115 162
434 t 116 163 163 163 116 163
435 u 117 164 164 164 117 164
436 v 118 165 165 165 118 165
437 w 119 166 166 166 119 166
438 x 120 167 167 167 120 167
439 y 121 168 168 168 121 168
440 z 122 169 169 169 122 169
441 { 123 192 192 251 123 192 ###
442 | 124 79 79 79 124 79
443 } 125 208 208 253 125 208 ###
444 ~ 126 161 161 255 126 161 ###
445 <DELETE> 127 7 7 7 127 7
446 <C1 0> 128 32 32 32 194.128 32
447 <C1 1> 129 33 33 33 194.129 33
448 <C1 2> 130 34 34 34 194.130 34
449 <C1 3> 131 35 35 35 194.131 35
450 <C1 4> 132 36 36 36 194.132 36
451 <C1 5> 133 21 37 37 194.133 37 ***
452 <C1 6> 134 6 6 6 194.134 6
453 <C1 7> 135 23 23 23 194.135 23
454 <C1 8> 136 40 40 40 194.136 40
455 <C1 9> 137 41 41 41 194.137 41
456 <C1 10> 138 42 42 42 194.138 42
457 <C1 11> 139 43 43 43 194.139 43
458 <C1 12> 140 44 44 44 194.140 44
459 <C1 13> 141 9 9 9 194.141 9
460 <C1 14> 142 10 10 10 194.142 10
461 <C1 15> 143 27 27 27 194.143 27
462 <C1 16> 144 48 48 48 194.144 48
463 <C1 17> 145 49 49 49 194.145 49
464 <C1 18> 146 26 26 26 194.146 26
465 <C1 19> 147 51 51 51 194.147 51
466 <C1 20> 148 52 52 52 194.148 52
467 <C1 21> 149 53 53 53 194.149 53
468 <C1 22> 150 54 54 54 194.150 54
469 <C1 23> 151 8 8 8 194.151 8
470 <C1 24> 152 56 56 56 194.152 56
471 <C1 25> 153 57 57 57 194.153 57
472 <C1 26> 154 58 58 58 194.154 58
473 <C1 27> 155 59 59 59 194.155 59
474 <C1 28> 156 4 4 4 194.156 4
475 <C1 29> 157 20 20 20 194.157 20
476 <C1 30> 158 62 62 62 194.158 62
477 <C1 31> 159 255 255 95 194.159 255 ###
478 <NON-BREAKING SPACE> 160 65 65 65 194.160 128.65
479 <INVERTED EXCLAMATION MARK> 161 170 170 170 194.161 128.66
480 <CENT SIGN> 162 74 74 176 194.162 128.67 ###
481 <POUND SIGN> 163 177 177 177 194.163 128.68
482 <CURRENCY SIGN> 164 159 159 159 194.164 128.69
483 <YEN SIGN> 165 178 178 178 194.165 128.70
484 <BROKEN BAR> 166 106 106 208 194.166 128.71 ###
485 <SECTION SIGN> 167 181 181 181 194.167 128.72
486 <DIAERESIS> 168 189 187 121 194.168 128.73 *** ###
487 <COPYRIGHT SIGN> 169 180 180 180 194.169 128.74
488 <FEMININE ORDINAL INDICATOR> 170 154 154 154 194.170 128.81
489 <LEFT POINTING GUILLEMET> 171 138 138 138 194.171 128.82
490 <NOT SIGN> 172 95 176 186 194.172 128.83 *** ###
491 <SOFT HYPHEN> 173 202 202 202 194.173 128.84
492 <REGISTERED TRADE MARK SIGN> 174 175 175 175 194.174 128.85
493 <MACRON> 175 188 188 161 194.175 128.86 ###
494 <DEGREE SIGN> 176 144 144 144 194.176 128.87
495 <PLUS-OR-MINUS SIGN> 177 143 143 143 194.177 128.88
496 <SUPERSCRIPT TWO> 178 234 234 234 194.178 128.89
497 <SUPERSCRIPT THREE> 179 250 250 250 194.179 128.98
498 <ACUTE ACCENT> 180 190 190 190 194.180 128.99
499 <MICRO SIGN> 181 160 160 160 194.181 128.100
500 <PARAGRAPH SIGN> 182 182 182 182 194.182 128.101
501 <MIDDLE DOT> 183 179 179 179 194.183 128.102
502 <CEDILLA> 184 157 157 157 194.184 128.103
503 <SUPERSCRIPT ONE> 185 218 218 218 194.185 128.104
504 <MASC. ORDINAL INDICATOR> 186 155 155 155 194.186 128.105
505 <RIGHT POINTING GUILLEMET> 187 139 139 139 194.187 128.106
506 <FRACTION ONE QUARTER> 188 183 183 183 194.188 128.112
507 <FRACTION ONE HALF> 189 184 184 184 194.189 128.113
508 <FRACTION THREE QUARTERS> 190 185 185 185 194.190 128.114
509 <INVERTED QUESTION MARK> 191 171 171 171 194.191 128.115
510 <A WITH GRAVE> 192 100 100 100 195.128 138.65
511 <A WITH ACUTE> 193 101 101 101 195.129 138.66
512 <A WITH CIRCUMFLEX> 194 98 98 98 195.130 138.67
513 <A WITH TILDE> 195 102 102 102 195.131 138.68
514 <A WITH DIAERESIS> 196 99 99 99 195.132 138.69
515 <A WITH RING ABOVE> 197 103 103 103 195.133 138.70
516 <CAPITAL LIGATURE AE> 198 158 158 158 195.134 138.71
517 <C WITH CEDILLA> 199 104 104 104 195.135 138.72
518 <E WITH GRAVE> 200 116 116 116 195.136 138.73
519 <E WITH ACUTE> 201 113 113 113 195.137 138.74
520 <E WITH CIRCUMFLEX> 202 114 114 114 195.138 138.81
521 <E WITH DIAERESIS> 203 115 115 115 195.139 138.82
522 <I WITH GRAVE> 204 120 120 120 195.140 138.83
523 <I WITH ACUTE> 205 117 117 117 195.141 138.84
524 <I WITH CIRCUMFLEX> 206 118 118 118 195.142 138.85
525 <I WITH DIAERESIS> 207 119 119 119 195.143 138.86
526 <CAPITAL LETTER ETH> 208 172 172 172 195.144 138.87
527 <N WITH TILDE> 209 105 105 105 195.145 138.88
528 <O WITH GRAVE> 210 237 237 237 195.146 138.89
529 <O WITH ACUTE> 211 238 238 238 195.147 138.98
530 <O WITH CIRCUMFLEX> 212 235 235 235 195.148 138.99
531 <O WITH TILDE> 213 239 239 239 195.149 138.100
532 <O WITH DIAERESIS> 214 236 236 236 195.150 138.101
533 <MULTIPLICATION SIGN> 215 191 191 191 195.151 138.102
534 <O WITH STROKE> 216 128 128 128 195.152 138.103
535 <U WITH GRAVE> 217 253 253 224 195.153 138.104 ###
536 <U WITH ACUTE> 218 254 254 254 195.154 138.105
537 <U WITH CIRCUMFLEX> 219 251 251 221 195.155 138.106 ###
538 <U WITH DIAERESIS> 220 252 252 252 195.156 138.112
539 <Y WITH ACUTE> 221 173 186 173 195.157 138.113 *** ###
540 <CAPITAL LETTER THORN> 222 174 174 174 195.158 138.114
541 <SMALL LETTER SHARP S> 223 89 89 89 195.159 138.115
542 <a WITH GRAVE> 224 68 68 68 195.160 139.65
543 <a WITH ACUTE> 225 69 69 69 195.161 139.66
544 <a WITH CIRCUMFLEX> 226 66 66 66 195.162 139.67
545 <a WITH TILDE> 227 70 70 70 195.163 139.68
546 <a WITH DIAERESIS> 228 67 67 67 195.164 139.69
547 <a WITH RING ABOVE> 229 71 71 71 195.165 139.70
548 <SMALL LIGATURE ae> 230 156 156 156 195.166 139.71
549 <c WITH CEDILLA> 231 72 72 72 195.167 139.72
550 <e WITH GRAVE> 232 84 84 84 195.168 139.73
551 <e WITH ACUTE> 233 81 81 81 195.169 139.74
552 <e WITH CIRCUMFLEX> 234 82 82 82 195.170 139.81
553 <e WITH DIAERESIS> 235 83 83 83 195.171 139.82
554 <i WITH GRAVE> 236 88 88 88 195.172 139.83
555 <i WITH ACUTE> 237 85 85 85 195.173 139.84
556 <i WITH CIRCUMFLEX> 238 86 86 86 195.174 139.85
557 <i WITH DIAERESIS> 239 87 87 87 195.175 139.86
558 <SMALL LETTER eth> 240 140 140 140 195.176 139.87
559 <n WITH TILDE> 241 73 73 73 195.177 139.88
560 <o WITH GRAVE> 242 205 205 205 195.178 139.89
561 <o WITH ACUTE> 243 206 206 206 195.179 139.98
562 <o WITH CIRCUMFLEX> 244 203 203 203 195.180 139.99
563 <o WITH TILDE> 245 207 207 207 195.181 139.100
564 <o WITH DIAERESIS> 246 204 204 204 195.182 139.101
565 <DIVISION SIGN> 247 225 225 225 195.183 139.102
566 <o WITH STROKE> 248 112 112 112 195.184 139.103
567 <u WITH GRAVE> 249 221 221 192 195.185 139.104 ###
568 <u WITH ACUTE> 250 222 222 222 195.186 139.105
569 <u WITH CIRCUMFLEX> 251 219 219 219 195.187 139.106
570 <u WITH DIAERESIS> 252 220 220 220 195.188 139.112
571 <y WITH ACUTE> 253 141 141 141 195.189 139.113
572 <SMALL LETTER thorn> 254 142 142 142 195.190 139.114
573 <y WITH DIAERESIS> 255 223 223 223 195.191 139.115
d396a558 574
575If you would rather see the above table in CCSID 0037 order rather than
576ASCII + Latin-1 order then run the table through:
577
578=over 4
579
395f5a0c 580=item recipe 4
d396a558 581
582=back
583
84f709e7 584 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}/)'\
585 -e '{push(@l,$_)}' \
586 -e 'END{print map{$_->[0]}' \
587 -e ' sort{$a->[1] <=> $b->[1]}' \
588 -e ' map{[$_,substr($_,42,3)]}@l;}' perlebcdic.pod
d396a558 589
590If you would rather see it in CCSID 1047 order then change the digit
59142 in the last line to 51, like this:
592
593=over 4
594
395f5a0c 595=item recipe 5
d396a558 596
597=back
598
84f709e7 599 perl -ne 'if(/.{33}\d{1,3}\s{6,8}\d{1,3}\s{6,8}\d{1,3}\s{6,8}\d{1,3}/)'\
600 -e '{push(@l,$_)}' \
601 -e 'END{print map{$_->[0]}' \
602 -e ' sort{$a->[1] <=> $b->[1]}' \
603 -e ' map{[$_,substr($_,51,3)]}@l;}' perlebcdic.pod
d396a558 604
605If you would rather see it in POSIX-BC order then change the digit
60651 in the last line to 60, like this:
607
608=over 4
609
395f5a0c 610=item recipe 6
d396a558 611
612=back
613
84f709e7 614 perl -ne 'if(/.{33}\d{1,3}\s{6,8}\d{1,3}\s{6,8}\d{1,3}\s{6,8}\d{1,3}/)'\
615 -e '{push(@l,$_)}' \
616 -e 'END{print map{$_->[0]}' \
617 -e ' sort{$a->[1] <=> $b->[1]}' \
618 -e ' map{[$_,substr($_,60,3)]}@l;}' perlebcdic.pod
d396a558 619
620
621=head1 IDENTIFYING CHARACTER CODE SETS
622
623To determine the character set you are running under from perl one
624could use the return value of ord() or chr() to test one or more
625character values. For example:
626
84f709e7 627 $is_ascii = "A" eq chr(65);
628 $is_ebcdic = "A" eq chr(193);
d396a558 629
51b5cecb 630Also, "\t" is a C<HORIZONTAL TABULATION> character so that:
d396a558 631
84f709e7 632 $is_ascii = ord("\t") == 9;
633 $is_ebcdic = ord("\t") == 5;
d396a558 634
635To distinguish EBCDIC code pages try looking at one or more of
636the characters that differ between them. For example:
637
84f709e7 638 $is_ebcdic_37 = "\n" eq chr(37);
639 $is_ebcdic_1047 = "\n" eq chr(21);
d396a558 640
641Or better still choose a character that is uniquely encoded in any
642of the code sets, e.g.:
643
84f709e7 644 $is_ascii = ord('[') == 91;
645 $is_ebcdic_37 = ord('[') == 186;
646 $is_ebcdic_1047 = ord('[') == 173;
647 $is_ebcdic_POSIX_BC = ord('[') == 187;
d396a558 648
649However, it would be unwise to write tests such as:
650
84f709e7 651 $is_ascii = "\r" ne chr(13); # WRONG
652 $is_ascii = "\n" ne chr(10); # ILL ADVISED
d396a558 653
2bbc8d55 654Obviously the first of these will fail to distinguish most ASCII platforms
655from either a CCSID 0037, a 1047, or a POSIX-BC EBCDIC platform since "\r" eq
84f709e7 656chr(13) under all of those coded character sets. But note too that
657because "\n" is chr(13) and "\r" is chr(10) on the MacIntosh (which is an
2bbc8d55 658ASCII platform) the second C<$is_ascii> test will lead to trouble there.
d396a558 659
84f709e7 660To determine whether or not perl was built under an EBCDIC
d396a558 661code page you can use the Config module like so:
662
663 use Config;
84f709e7 664 $is_ebcdic = $Config{'ebcdic'} eq 'define';
d396a558 665
666=head1 CONVERSIONS
667
1e054b24 668=head2 tr///
669
d396a558 670In order to convert a string of characters from one character set to
671another a simple list of numbers, such as in the right columns in the
672above table, along with perl's tr/// operator is all that is needed.
673The data in the table are in ASCII order hence the EBCDIC columns
674provide easy to use ASCII to EBCDIC operations that are also easily
675reversed.
676
84f709e7 677For example, to convert ASCII to code page 037 take the output of the second
678column from the output of recipe 0 (modified to add \\ characters) and use
d5d9880c 679it in tr/// like so:
d396a558 680
84f709e7 681 $cp_037 =
682 '\000\001\002\003\234\011\206\177\227\215\216\013\014\015\016\017' .
683 '\020\021\022\023\235\205\010\207\030\031\222\217\034\035\036\037' .
684 '\200\201\202\203\204\012\027\033\210\211\212\213\214\005\006\007' .
685 '\220\221\026\223\224\225\226\004\230\231\232\233\024\025\236\032' .
686 '\040\240\342\344\340\341\343\345\347\361\242\056\074\050\053\174' .
687 '\046\351\352\353\350\355\356\357\354\337\041\044\052\051\073\254' .
688 '\055\057\302\304\300\301\303\305\307\321\246\054\045\137\076\077' .
689 '\370\311\312\313\310\315\316\317\314\140\072\043\100\047\075\042' .
690 '\330\141\142\143\144\145\146\147\150\151\253\273\360\375\376\261' .
691 '\260\152\153\154\155\156\157\160\161\162\252\272\346\270\306\244' .
692 '\265\176\163\164\165\166\167\170\171\172\241\277\320\335\336\256' .
693 '\136\243\245\267\251\247\266\274\275\276\133\135\257\250\264\327' .
694 '\173\101\102\103\104\105\106\107\110\111\255\364\366\362\363\365' .
695 '\175\112\113\114\115\116\117\120\121\122\271\373\374\371\372\377' .
696 '\134\367\123\124\125\126\127\130\131\132\262\324\326\322\323\325' .
697 '\060\061\062\063\064\065\066\067\070\071\263\333\334\331\332\237' ;
d396a558 698
699 my $ebcdic_string = $ascii_string;
d7449b02 700 eval '$ebcdic_string =~ tr/' . $cp_037 . '/\000-\377/';
d396a558 701
d5d9880c 702To convert from EBCDIC 037 to ASCII just reverse the order of the tr///
d396a558 703arguments like so:
704
705 my $ascii_string = $ebcdic_string;
d7449b02 706 eval '$ascii_string =~ tr/\000-\377/' . $cp_037 . '/';
d5d9880c 707
708Similarly one could take the output of the third column from recipe 0 to
709obtain a C<$cp_1047> table. The fourth column of the output from recipe
7100 could provide a C<$cp_posix_bc> table suitable for transcoding as well.
1e054b24 711
712=head2 iconv
d396a558 713
d5d9880c 714XPG operability often implies the presence of an I<iconv> utility
d396a558 715available from the shell or from the C library. Consult your system's
716documentation for information on iconv.
717
3958b146 718On OS/390 or z/OS see the iconv(1) manpage. One way to invoke the iconv
d396a558 719shell utility from within perl would be to:
720
395f5a0c 721 # OS/390 or z/OS example
84f709e7 722 $ascii_data = `echo '$ebcdic_data'| iconv -f IBM-1047 -t ISO8859-1`
d396a558 723
724or the inverse map:
725
395f5a0c 726 # OS/390 or z/OS example
84f709e7 727 $ebcdic_data = `echo '$ascii_data'| iconv -f ISO8859-1 -t IBM-1047`
d396a558 728
d396a558 729For other perl based conversion options see the Convert::* modules on CPAN.
730
1e054b24 731=head2 C RTL
732
395f5a0c 733The OS/390 and z/OS C run time libraries provide _atoe() and _etoa() functions.
1e054b24 734
d396a558 735=head1 OPERATOR DIFFERENCES
736
737The C<..> range operator treats certain character ranges with
2bbc8d55 738care on EBCDIC platforms. For example the following array
739will have twenty six elements on either an EBCDIC platform
740or an ASCII platform:
d396a558 741
84f709e7 742 @alphabet = ('A'..'Z'); # $#alphabet == 25
d396a558 743
744The bitwise operators such as & ^ | may return different results
745when operating on string or character data in a perl program running
2bbc8d55 746on an EBCDIC platform than when run on an ASCII platform. Here is
d396a558 747an example adapted from the one in L<perlop>:
748
749 # EBCDIC-based examples
84f709e7 750 print "j p \n" ^ " a h"; # prints "JAPH\n"
751 print "JA" | " ph\n"; # prints "japh\n"
752 print "JAPH\nJunk" & "\277\277\277\277\277"; # prints "japh\n";
753 print 'p N$' ^ " E<H\n"; # prints "Perl\n";
d396a558 754
755An interesting property of the 32 C0 control characters
756in the ASCII table is that they can "literally" be constructed
51b5cecb 757as control characters in perl, e.g. C<(chr(0) eq "\c@")>
2bbc8d55 758C<(chr(1) eq "\cA")>, and so on. Perl on EBCDIC platforms has been
51b5cecb 759ported to take "\c@" to chr(0) and "\cA" to chr(1) as well, but the
d396a558 760thirty three characters that result depend on which code page you are
761using. The table below uses the character names from the previous table
51b5cecb 762but with substitutions such as s/START OF/S.O./; s/END OF /E.O./;
d396a558 763s/TRANSMISSION/TRANS./; s/TABULATION/TAB./; s/VERTICAL/VERT./;
764s/HORIZONTAL/HORIZ./; s/DEVICE CONTROL/D.C./; s/SEPARATOR/SEP./;
765s/NEGATIVE ACKNOWLEDGE/NEG. ACK./;. The POSIX-BC and 1047 sets are
766identical throughout this range and differ from the 0037 set at only
51b5cecb 767one spot (21 decimal). Note that the C<LINE FEED> character
2bbc8d55 768may be generated by "\cJ" on ASCII platforms but by "\cU" on 1047 or POSIX-BC
769platforms and cannot be generated as a C<"\c.letter."> control character on
7700037 platforms. Note also that "\c\\" maps to two characters
d396a558 771not one.
772
773 chr ord 8859-1 0037 1047 && POSIX-BC
774 ------------------------------------------------------------------------
775 "\c?" 127 <DELETE> " " ***><
776 "\c@" 0 <NULL> <NULL> <NULL> ***><
777 "\cA" 1 <S.O. HEADING> <S.O. HEADING> <S.O. HEADING>
778 "\cB" 2 <S.O. TEXT> <S.O. TEXT> <S.O. TEXT>
779 "\cC" 3 <E.O. TEXT> <E.O. TEXT> <E.O. TEXT>
780 "\cD" 4 <E.O. TRANS.> <C1 28> <C1 28>
781 "\cE" 5 <ENQUIRY> <HORIZ. TAB.> <HORIZ. TAB.>
782 "\cF" 6 <ACKNOWLEDGE> <C1 6> <C1 6>
783 "\cG" 7 <BELL> <DELETE> <DELETE>
784 "\cH" 8 <BACKSPACE> <C1 23> <C1 23>
785 "\cI" 9 <HORIZ. TAB.> <C1 13> <C1 13>
786 "\cJ" 10 <LINE FEED> <C1 14> <C1 14>
787 "\cK" 11 <VERT. TAB.> <VERT. TAB.> <VERT. TAB.>
788 "\cL" 12 <FORM FEED> <FORM FEED> <FORM FEED>
789 "\cM" 13 <CARRIAGE RETURN> <CARRIAGE RETURN> <CARRIAGE RETURN>
790 "\cN" 14 <SHIFT OUT> <SHIFT OUT> <SHIFT OUT>
791 "\cO" 15 <SHIFT IN> <SHIFT IN> <SHIFT IN>
792 "\cP" 16 <DATA LINK ESCAPE> <DATA LINK ESCAPE> <DATA LINK ESCAPE>
793 "\cQ" 17 <D.C. ONE> <D.C. ONE> <D.C. ONE>
794 "\cR" 18 <D.C. TWO> <D.C. TWO> <D.C. TWO>
795 "\cS" 19 <D.C. THREE> <D.C. THREE> <D.C. THREE>
796 "\cT" 20 <D.C. FOUR> <C1 29> <C1 29>
797 "\cU" 21 <NEG. ACK.> <C1 5> <LINE FEED> ***
798 "\cV" 22 <SYNCHRONOUS IDLE> <BACKSPACE> <BACKSPACE>
799 "\cW" 23 <E.O. TRANS. BLOCK> <C1 7> <C1 7>
800 "\cX" 24 <CANCEL> <CANCEL> <CANCEL>
801 "\cY" 25 <E.O. MEDIUM> <E.O. MEDIUM> <E.O. MEDIUM>
802 "\cZ" 26 <SUBSTITUTE> <C1 18> <C1 18>
803 "\c[" 27 <ESCAPE> <C1 15> <C1 15>
804 "\c\\" 28 <FILE SEP.>\ <FILE SEP.>\ <FILE SEP.>\
805 "\c]" 29 <GROUP SEP.> <GROUP SEP.> <GROUP SEP.>
806 "\c^" 30 <RECORD SEP.> <RECORD SEP.> <RECORD SEP.> ***><
807 "\c_" 31 <UNIT SEP.> <UNIT SEP.> <UNIT SEP.> ***><
808
809
810=head1 FUNCTION DIFFERENCES
811
812=over 8
813
814=item chr()
815
816chr() must be given an EBCDIC code number argument to yield a desired
2bbc8d55 817character return value on an EBCDIC platform. For example:
d396a558 818
84f709e7 819 $CAPITAL_LETTER_A = chr(193);
d396a558 820
821=item ord()
822
2bbc8d55 823ord() will return EBCDIC code number values on an EBCDIC platform.
d396a558 824For example:
825
84f709e7 826 $the_number_193 = ord("A");
d396a558 827
828=item pack()
829
830The c and C templates for pack() are dependent upon character set
831encoding. Examples of usage on EBCDIC include:
832
833 $foo = pack("CCCC",193,194,195,196);
834 # $foo eq "ABCD"
84f709e7 835 $foo = pack("C4",193,194,195,196);
d396a558 836 # same thing
837
838 $foo = pack("ccxxcc",193,194,195,196);
839 # $foo eq "AB\0\0CD"
840
841=item print()
842
843One must be careful with scalars and strings that are passed to
844print that contain ASCII encodings. One common place
845for this to occur is in the output of the MIME type header for
846CGI script writing. For example, many perl programming guides
847recommend something similar to:
848
849 print "Content-type:\ttext/html\015\012\015\012";
850 # this may be wrong on EBCDIC
851
395f5a0c 852Under the IBM OS/390 USS Web Server or WebSphere on z/OS for example
853you should instead write that as:
d396a558 854
855 print "Content-type:\ttext/html\r\n\r\n"; # OK for DGW et alia
856
857That is because the translation from EBCDIC to ASCII is done
858by the web server in this case (such code will not be appropriate for
859the Macintosh however). Consult your web server's documentation for
860further details.
861
862=item printf()
863
864The formats that can convert characters to numbers and vice versa
865will be different from their ASCII counterparts when executed
2bbc8d55 866on an EBCDIC platform. Examples include:
d396a558 867
868 printf("%c%c%c",193,194,195); # prints ABC
869
870=item sort()
871
872EBCDIC sort results may differ from ASCII sort results especially for
873mixed case strings. This is discussed in more detail below.
874
875=item sprintf()
876
877See the discussion of printf() above. An example of the use
878of sprintf would be:
879
84f709e7 880 $CAPITAL_LETTER_A = sprintf("%c",193);
d396a558 881
882=item unpack()
883
884See the discussion of pack() above.
885
886=back
887
888=head1 REGULAR EXPRESSION DIFFERENCES
889
890As of perl 5.005_03 the letter range regular expression such as
891[A-Z] and [a-z] have been especially coded to not pick up gap
b3b6085d 892characters. For example, characters such as E<ocirc> C<o WITH CIRCUMFLEX>
893that lie between I and J would not be matched by the
1b2d223b 894regular expression range C</[H-K]/>. This works in
895the other direction, too, if either of the range end points is
896explicitly numeric: C<[\x89-\x91]> will match C<\x8e>, even
897though C<\x89> is C<i> and C<\x91 > is C<j>, and C<\x8e>
898is a gap character from the alphabetic viewpoint.
51b5cecb 899
900If you do want to match the alphabet gap characters in a single octet
d396a558 901regular expression try matching the hex or octal code such
2bbc8d55 902as C</\313/> on EBCDIC or C</\364/> on ASCII platforms to
51b5cecb 903have your regular expression match C<o WITH CIRCUMFLEX>.
d396a558 904
51b5cecb 905Another construct to be wary of is the inappropriate use of hex or
d396a558 906octal constants in regular expressions. Consider the following
907set of subs:
908
909 sub is_c0 {
910 my $char = substr(shift,0,1);
911 $char =~ /[\000-\037]/;
912 }
913
914 sub is_print_ascii {
915 my $char = substr(shift,0,1);
916 $char =~ /[\040-\176]/;
917 }
918
919 sub is_delete {
920 my $char = substr(shift,0,1);
921 $char eq "\177";
922 }
923
924 sub is_c1 {
925 my $char = substr(shift,0,1);
926 $char =~ /[\200-\237]/;
927 }
928
929 sub is_latin_1 {
930 my $char = substr(shift,0,1);
931 $char =~ /[\240-\377]/;
932 }
933
51b5cecb 934The above would be adequate if the concern was only with numeric code points.
935However, the concern may be with characters rather than code points
2bbc8d55 936and on an EBCDIC platform it may be desirable for constructs such as
d396a558 937C<if (is_print_ascii("A")) {print "A is a printable character\n";}> to print
938out the expected message. One way to represent the above collection
939of character classification subs that is capable of working across the
940four coded character sets discussed in this document is as follows:
941
942 sub Is_c0 {
943 my $char = substr(shift,0,1);
84f709e7 944 if (ord('^')==94) { # ascii
d396a558 945 return $char =~ /[\000-\037]/;
84f709e7 946 }
947 if (ord('^')==176) { # 37
d396a558 948 return $char =~ /[\000-\003\067\055-\057\026\005\045\013-\023\074\075\062\046\030\031\077\047\034-\037]/;
949 }
84f709e7 950 if (ord('^')==95 || ord('^')==106) { # 1047 || posix-bc
d396a558 951 return $char =~ /[\000-\003\067\055-\057\026\005\025\013-\023\074\075\062\046\030\031\077\047\034-\037]/;
952 }
953 }
954
955 sub Is_print_ascii {
956 my $char = substr(shift,0,1);
957 $char =~ /[ !"\#\$%&'()*+,\-.\/0-9:;<=>?\@A-Z[\\\]^_`a-z{|}~]/;
958 }
959
960 sub Is_delete {
961 my $char = substr(shift,0,1);
84f709e7 962 if (ord('^')==94) { # ascii
d396a558 963 return $char eq "\177";
84f709e7 964 }
965 else { # ebcdic
d396a558 966 return $char eq "\007";
967 }
968 }
969
970 sub Is_c1 {
971 my $char = substr(shift,0,1);
84f709e7 972 if (ord('^')==94) { # ascii
d396a558 973 return $char =~ /[\200-\237]/;
974 }
84f709e7 975 if (ord('^')==176) { # 37
d396a558 976 return $char =~ /[\040-\044\025\006\027\050-\054\011\012\033\060\061\032\063-\066\010\070-\073\040\024\076\377]/;
977 }
84f709e7 978 if (ord('^')==95) { # 1047
d396a558 979 return $char =~ /[\040-\045\006\027\050-\054\011\012\033\060\061\032\063-\066\010\070-\073\040\024\076\377]/;
980 }
84f709e7 981 if (ord('^')==106) { # posix-bc
982 return $char =~
d396a558 983 /[\040-\045\006\027\050-\054\011\012\033\060\061\032\063-\066\010\070-\073\040\024\076\137]/;
984 }
985 }
986
987 sub Is_latin_1 {
988 my $char = substr(shift,0,1);
84f709e7 989 if (ord('^')==94) { # ascii
d396a558 990 return $char =~ /[\240-\377]/;
991 }
84f709e7 992 if (ord('^')==176) { # 37
993 return $char =~
d396a558 994 /[\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]/;
995 }
84f709e7 996 if (ord('^')==95) { # 1047
d396a558 997 return $char =~
998 /[\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]/;
999 }
84f709e7 1000 if (ord('^')==106) { # posix-bc
1001 return $char =~
d396a558 1002 /[\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]/;
1003 }
1004 }
1005
1006Note however that only the C<Is_ascii_print()> sub is really independent
1007of coded character set. Another way to write C<Is_latin_1()> would be
1008to use the characters in the range explicitly:
1009
1010 sub Is_latin_1 {
1011 my $char = substr(shift,0,1);
1012 $char =~ /[ ¡¢£¤¥¦§¨©ª«¬­®¯°±²³´µ¶·¸¹º»¼½¾¿ÀÁÂÃÄÅÆÇÈÉÊËÌÍÎÏÐÑÒÓÔÕÖ×ØÙÚÛÜÝÞßàáâãäåæçèéêëìíîïðñòóôõö÷øùúûüýþÿ]/;
1013 }
1014
1015Although that form may run into trouble in network transit (due to the
1016presence of 8 bit characters) or on non ISO-Latin character sets.
d396a558 1017
1018=head1 SOCKETS
1019
1020Most socket programming assumes ASCII character encodings in network
1021byte order. Exceptions can include CGI script writing under a
1022host web server where the server may take care of translation for you.
1023Most host web servers convert EBCDIC data to ISO-8859-1 or Unicode on
1024output.
1025
1026=head1 SORTING
1027
1028One big difference between ASCII based character sets and EBCDIC ones
1029are the relative positions of upper and lower case letters and the
2bbc8d55 1030letters compared to the digits. If sorted on an ASCII based platform the
d396a558 1031two letter abbreviation for a physician comes before the two letter
1032for drive, that is:
1033
84f709e7 1034 @sorted = sort(qw(Dr. dr.)); # @sorted holds ('Dr.','dr.') on ASCII,
1035 # but ('dr.','Dr.') on EBCDIC
d396a558 1036
1037The property of lower case before uppercase letters in EBCDIC is
1038even carried to the Latin 1 EBCDIC pages such as 0037 and 1047.
b3b6085d 1039An example would be that E<Euml> C<E WITH DIAERESIS> (203) comes
2bbc8d55 1040before E<euml> C<e WITH DIAERESIS> (235) on an ASCII platform, but
1041the latter (83) comes before the former (115) on an EBCDIC platform.
b3b6085d 1042(Astute readers will note that the upper case version of E<szlig>
51b5cecb 1043C<SMALL LETTER SHARP S> is simply "SS" and that the upper case version of
b3b6085d 1044E<yuml> C<y WITH DIAERESIS> is not in the 0..255 range but it is
51b5cecb 1045at U+x0178 in Unicode, or C<"\x{178}"> in a Unicode enabled Perl).
d396a558 1046
1047The sort order will cause differences between results obtained on
2bbc8d55 1048ASCII platforms versus EBCDIC platforms. What follows are some suggestions
d396a558 1049on how to deal with these differences.
1050
51b5cecb 1051=head2 Ignore ASCII vs. EBCDIC sort differences.
d396a558 1052
1053This is the least computationally expensive strategy. It may require
1054some user education.
1055
51b5cecb 1056=head2 MONO CASE then sort data.
d396a558 1057
51b5cecb 1058In order to minimize the expense of mono casing mixed test try to
d396a558 1059C<tr///> towards the character set case most employed within the data.
1060If the data are primarily UPPERCASE non Latin 1 then apply tr/[a-z]/[A-Z]/
1061then sort(). If the data are primarily lowercase non Latin 1 then
1062apply tr/[A-Z]/[a-z]/ before sorting. If the data are primarily UPPERCASE
51b5cecb 1063and include Latin-1 characters then apply:
1064
84f709e7 1065 tr/[a-z]/[A-Z]/;
51b5cecb 1066 tr/[àáâãäåæçèéêëìíîïðñòóôõöøùúûüýþ]/[ÀÁÂÃÄÅÆÇÈÉÊËÌÍÎÏÐÑÒÓÔÕÖØÙÚÛÜÝÞ]/;
84f709e7 1067 s/ß/SS/g;
d396a558 1068
51b5cecb 1069then sort(). Do note however that such Latin-1 manipulation does not
b3b6085d 1070address the E<yuml> C<y WITH DIAERESIS> character that will remain at
2bbc8d55 1071code point 255 on ASCII platforms, but 223 on most EBCDIC platforms
51b5cecb 1072where it will sort to a place less than the EBCDIC numerals. With a
1073Unicode enabled Perl you might try:
d396a558 1074
51b5cecb 1075 tr/^?/\x{178}/;
1076
1077The strategy of mono casing data before sorting does not preserve the case
1078of the data and may not be acceptable for that reason.
1079
1080=head2 Convert, sort data, then re convert.
d396a558 1081
1082This is the most expensive proposition that does not employ a network
1083connection.
1084
2bbc8d55 1085=head2 Perform sorting on one type of platform only.
d396a558 1086
1087This strategy can employ a network connection. As such
1088it would be computationally expensive.
1089
395f5a0c 1090=head1 TRANSFORMATION FORMATS
1e054b24 1091
1092There are a variety of ways of transforming data with an intra character set
1093mapping that serve a variety of purposes. Sorting was discussed in the
1094previous section and a few of the other more popular mapping techniques are
1095discussed next.
1096
1097=head2 URL decoding and encoding
d396a558 1098
51b5cecb 1099Note that some URLs have hexadecimal ASCII code points in them in an
1e054b24 1100attempt to overcome character or protocol limitation issues. For example
1101the tilde character is not on every keyboard hence a URL of the form:
d396a558 1102
1103 http://www.pvhp.com/~pvhp/
1104
1105may also be expressed as either of:
1106
1107 http://www.pvhp.com/%7Epvhp/
1108
1109 http://www.pvhp.com/%7epvhp/
1110
51b5cecb 1111where 7E is the hexadecimal ASCII code point for '~'. Here is an example
d396a558 1112of decoding such a URL under CCSID 1047:
1113
84f709e7 1114 $url = 'http://www.pvhp.com/%7Epvhp/';
d396a558 1115 # this array assumes code page 1047
1116 my @a2e_1047 = (
1117 0, 1, 2, 3, 55, 45, 46, 47, 22, 5, 21, 11, 12, 13, 14, 15,
1118 16, 17, 18, 19, 60, 61, 50, 38, 24, 25, 63, 39, 28, 29, 30, 31,
1119 64, 90,127,123, 91,108, 80,125, 77, 93, 92, 78,107, 96, 75, 97,
1120 240,241,242,243,244,245,246,247,248,249,122, 94, 76,126,110,111,
1121 124,193,194,195,196,197,198,199,200,201,209,210,211,212,213,214,
1122 215,216,217,226,227,228,229,230,231,232,233,173,224,189, 95,109,
1123 121,129,130,131,132,133,134,135,136,137,145,146,147,148,149,150,
1124 151,152,153,162,163,164,165,166,167,168,169,192, 79,208,161, 7,
1125 32, 33, 34, 35, 36, 37, 6, 23, 40, 41, 42, 43, 44, 9, 10, 27,
1126 48, 49, 26, 51, 52, 53, 54, 8, 56, 57, 58, 59, 4, 20, 62,255,
1127 65,170, 74,177,159,178,106,181,187,180,154,138,176,202,175,188,
1128 144,143,234,250,190,160,182,179,157,218,155,139,183,184,185,171,
1129 100,101, 98,102, 99,103,158,104,116,113,114,115,120,117,118,119,
1130 172,105,237,238,235,239,236,191,128,253,254,251,252,186,174, 89,
1131 68, 69, 66, 70, 67, 71,156, 72, 84, 81, 82, 83, 88, 85, 86, 87,
1132 140, 73,205,206,203,207,204,225,112,221,222,219,220,141,142,223
1133 );
1134 $url =~ s/%([0-9a-fA-F]{2})/pack("c",$a2e_1047[hex($1)])/ge;
1135
1e054b24 1136Conversely, here is a partial solution for the task of encoding such
1137a URL under the 1047 code page:
1138
84f709e7 1139 $url = 'http://www.pvhp.com/~pvhp/';
1e054b24 1140 # this array assumes code page 1047
1141 my @e2a_1047 = (
1142 0, 1, 2, 3,156, 9,134,127,151,141,142, 11, 12, 13, 14, 15,
1143 16, 17, 18, 19,157, 10, 8,135, 24, 25,146,143, 28, 29, 30, 31,
1144 128,129,130,131,132,133, 23, 27,136,137,138,139,140, 5, 6, 7,
1145 144,145, 22,147,148,149,150, 4,152,153,154,155, 20, 21,158, 26,
1146 32,160,226,228,224,225,227,229,231,241,162, 46, 60, 40, 43,124,
1147 38,233,234,235,232,237,238,239,236,223, 33, 36, 42, 41, 59, 94,
1148 45, 47,194,196,192,193,195,197,199,209,166, 44, 37, 95, 62, 63,
1149 248,201,202,203,200,205,206,207,204, 96, 58, 35, 64, 39, 61, 34,
1150 216, 97, 98, 99,100,101,102,103,104,105,171,187,240,253,254,177,
1151 176,106,107,108,109,110,111,112,113,114,170,186,230,184,198,164,
1152 181,126,115,116,117,118,119,120,121,122,161,191,208, 91,222,174,
1153 172,163,165,183,169,167,182,188,189,190,221,168,175, 93,180,215,
1154 123, 65, 66, 67, 68, 69, 70, 71, 72, 73,173,244,246,242,243,245,
1155 125, 74, 75, 76, 77, 78, 79, 80, 81, 82,185,251,252,249,250,255,
1156 92,247, 83, 84, 85, 86, 87, 88, 89, 90,178,212,214,210,211,213,
1157 48, 49, 50, 51, 52, 53, 54, 55, 56, 57,179,219,220,217,218,159
1158 );
84f709e7 1159 # The following regular expression does not address the
1e054b24 1160 # mappings for: ('.' => '%2E', '/' => '%2F', ':' => '%3A')
1161 $url =~ s/([\t "#%&\(\),;<=>\?\@\[\\\]^`{|}~])/sprintf("%%%02X",$e2a_1047[ord($1)])/ge;
1162
1163where a more complete solution would split the URL into components
1164and apply a full s/// substitution only to the appropriate parts.
1165
1166In the remaining examples a @e2a or @a2e array may be employed
1167but the assignment will not be shown explicitly. For code page 1047
1168you could use the @a2e_1047 or @e2a_1047 arrays just shown.
1169
1170=head2 uu encoding and decoding
1171
1172The C<u> template to pack() or unpack() will render EBCDIC data in EBCDIC
1173characters equivalent to their ASCII counterparts. For example, the
1174following will print "Yes indeed\n" on either an ASCII or EBCDIC computer:
1175
84f709e7 1176 $all_byte_chrs = '';
1177 for (0..255) { $all_byte_chrs .= chr($_); }
1178 $uuencode_byte_chrs = pack('u', $all_byte_chrs);
210b36aa 1179 ($uu = <<'ENDOFHEREDOC') =~ s/^\s*//gm;
1e054b24 1180 M``$"`P0%!@<("0H+#`T.#Q`1$A,4%187&!D:&QP='A\@(2(C)"4F)R@I*BLL
1181 M+2XO,#$R,S0U-C<X.3H[/#T^/T!!0D-$149'2$E*2TQ-3D]045)35%565UA9
1182 M6EM<75Y?8&%B8V1E9F=H:6IK;&UN;W!Q<G-T=79W>'EZ>WQ]?G^`@8*#A(6&
1183 MAXB)BHN,C8Z/D)&2DY25EI>8F9J;G)V>GZ"AHJ.DI::GJ*FJJZRMKJ^PL;*S
1184 MM+6VM[BYNKN\O;Z_P,'"P\3%QL?(R<K+S,W.S]#1TM/4U=;7V-G:V]S=WM_@
1185 ?X>+CY.7FY^CIZNOL[>[O\/'R\_3U]O?X^?K[_/W^_P``
1186 ENDOFHEREDOC
84f709e7 1187 if ($uuencode_byte_chrs eq $uu) {
1e054b24 1188 print "Yes ";
1189 }
1190 $uudecode_byte_chrs = unpack('u', $uuencode_byte_chrs);
84f709e7 1191 if ($uudecode_byte_chrs eq $all_byte_chrs) {
1e054b24 1192 print "indeed\n";
1193 }
1194
1195Here is a very spartan uudecoder that will work on EBCDIC provided
1196that the @e2a array is filled in appropriately:
1197
84f709e7 1198 #!/usr/local/bin/perl
1199 @e2a = ( # this must be filled in
1200 );
1201 $_ = <> until ($mode,$file) = /^begin\s*(\d*)\s*(\S*)/;
1e054b24 1202 open(OUT, "> $file") if $file ne "";
1203 while(<>) {
1204 last if /^end/;
1205 next if /[a-z]/;
1206 next unless int(((($e2a[ord()] - 32 ) & 077) + 2) / 3) ==
1207 int(length() / 4);
1208 print OUT unpack("u", $_);
1209 }
1210 close(OUT);
1211 chmod oct($mode), $file;
1212
1213
1214=head2 Quoted-Printable encoding and decoding
1215
2bbc8d55 1216On ASCII encoded platforms it is possible to strip characters outside of
1e054b24 1217the printable set using:
1218
1219 # This QP encoder works on ASCII only
84f709e7 1220 $qp_string =~ s/([=\x00-\x1F\x80-\xFF])/sprintf("=%02X",ord($1))/ge;
1e054b24 1221
2bbc8d55 1222Whereas a QP encoder that works on both ASCII and EBCDIC platforms
1e054b24 1223would look somewhat like the following (where the EBCDIC branch @e2a
1224array is omitted for brevity):
1225
1226 if (ord('A') == 65) { # ASCII
1227 $delete = "\x7F"; # ASCII
1228 @e2a = (0 .. 255) # ASCII to ASCII identity map
84f709e7 1229 }
1230 else { # EBCDIC
1e054b24 1231 $delete = "\x07"; # EBCDIC
84f709e7 1232 @e2a = # EBCDIC to ASCII map (as shown above)
1e054b24 1233 }
84f709e7 1234 $qp_string =~
1e054b24 1235 s/([^ !"\#\$%&'()*+,\-.\/0-9:;<>?\@A-Z[\\\]^_`a-z{|}~$delete])/sprintf("=%02X",$e2a[ord($1)])/ge;
1236
1237(although in production code the substitutions might be done
1238in the EBCDIC branch with the @e2a array and separately in the
1239ASCII branch without the expense of the identity map).
1240
1241Such QP strings can be decoded with:
1242
1243 # This QP decoder is limited to ASCII only
1244 $string =~ s/=([0-9A-Fa-f][0-9A-Fa-f])/chr hex $1/ge;
1245 $string =~ s/=[\n\r]+$//;
1246
2bbc8d55 1247Whereas a QP decoder that works on both ASCII and EBCDIC platforms
1e054b24 1248would look somewhat like the following (where the @a2e array is
1249omitted for brevity):
1250
1251 $string =~ s/=([0-9A-Fa-f][0-9A-Fa-f])/chr $a2e[hex $1]/ge;
1252 $string =~ s/=[\n\r]+$//;
1253
395f5a0c 1254=head2 Caesarian ciphers
1e054b24 1255
1256The practice of shifting an alphabet one or more characters for encipherment
1257dates back thousands of years and was explicitly detailed by Gaius Julius
1258Caesar in his B<Gallic Wars> text. A single alphabet shift is sometimes
1259referred to as a rotation and the shift amount is given as a number $n after
1260the string 'rot' or "rot$n". Rot0 and rot26 would designate identity maps
1261on the 26 letter English version of the Latin alphabet. Rot13 has the
1262interesting property that alternate subsequent invocations are identity maps
1263(thus rot13 is its own non-trivial inverse in the group of 26 alphabet
1264rotations). Hence the following is a rot13 encoder and decoder that will
2bbc8d55 1265work on ASCII and EBCDIC platforms:
1e054b24 1266
1267 #!/usr/local/bin/perl
1268
84f709e7 1269 while(<>){
1e054b24 1270 tr/n-za-mN-ZA-M/a-zA-Z/;
1271 print;
1272 }
1273
1274In one-liner form:
1275
84f709e7 1276 perl -ne 'tr/n-za-mN-ZA-M/a-zA-Z/;print'
1e054b24 1277
1278
1279=head1 Hashing order and checksums
1280
395f5a0c 1281To the extent that it is possible to write code that depends on
1282hashing order there may be differences between hashes as stored
2bbc8d55 1283on an ASCII based platform and hashes stored on an EBCDIC based platform.
1e054b24 1284XXX
1285
d396a558 1286=head1 I18N AND L10N
1287
1288Internationalization(I18N) and localization(L10N) are supported at least
2bbc8d55 1289in principle even on EBCDIC platforms. The details are system dependent
d396a558 1290and discussed under the L<perlebcdic/OS ISSUES> section below.
1291
1292=head1 MULTI OCTET CHARACTER SETS
1293
395f5a0c 1294Perl may work with an internal UTF-EBCDIC encoding form for wide characters
1295on EBCDIC platforms in a manner analogous to the way that it works with
1296the UTF-8 internal encoding form on ASCII based platforms.
1297
1298Legacy multi byte EBCDIC code pages XXX.
d396a558 1299
1300=head1 OS ISSUES
1301
1302There may be a few system dependent issues
1303of concern to EBCDIC Perl programmers.
1304
522b859a 1305=head2 OS/400
51b5cecb 1306
d396a558 1307=over 8
1308
522b859a 1309=item PASE
1310
1311The PASE environment is runtime environment for OS/400 that can run
1312executables built for PowerPC AIX in OS/400, see L<perlos400>. PASE
1313is ASCII-based, not EBCDIC-based as the ILE.
1314
d396a558 1315=item IFS access
1316
1317XXX.
1318
1319=back
1320
395f5a0c 1321=head2 OS/390, z/OS
d396a558 1322
51b5cecb 1323Perl runs under Unix Systems Services or USS.
1324
d396a558 1325=over 8
1326
51b5cecb 1327=item chcp
1328
1e054b24 1329B<chcp> is supported as a shell utility for displaying and changing
1330one's code page. See also L<chcp>.
51b5cecb 1331
d396a558 1332=item dataset access
1333
1334For sequential data set access try:
1335
1336 my @ds_records = `cat //DSNAME`;
1337
1338or:
1339
1340 my @ds_records = `cat //'HLQ.DSNAME'`;
1341
1342See also the OS390::Stdio module on CPAN.
1343
395f5a0c 1344=item OS/390, z/OS iconv
51b5cecb 1345
1e054b24 1346B<iconv> is supported as both a shell utility and a C RTL routine.
1347See also the iconv(1) and iconv(3) manual pages.
51b5cecb 1348
d396a558 1349=item locales
1350
395f5a0c 1351On OS/390 or z/OS see L<locale> for information on locales. The L10N files
1352are in F</usr/nls/locale>. $Config{d_setlocale} is 'define' on OS/390
1353or z/OS.
d396a558 1354
1355=back
1356
1357=head2 VM/ESA?
1358
1359XXX.
1360
1361=head2 POSIX-BC?
1362
1363XXX.
1364
51b5cecb 1365=head1 BUGS
1366
1367This pod document contains literal Latin 1 characters and may encounter
b1866b2d 1368translation difficulties. In particular one popular nroff implementation
51b5cecb 1369was known to strip accented characters to their unaccented counterparts
1370while attempting to view this document through the B<pod2man> program
1371(for example, you may see a plain C<y> rather than one with a diaeresis
3958b146 1372as in E<yuml>). Another nroff truncated the resultant manpage at
395f5a0c 1373the first occurrence of 8 bit characters.
51b5cecb 1374
1375Not all shells will allow multiple C<-e> string arguments to perl to
395f5a0c 1376be concatenated together properly as recipes 0, 2, 4, 5, and 6 might
1377seem to imply.
51b5cecb 1378
b3b6085d 1379=head1 SEE ALSO
1380
395f5a0c 1381L<perllocale>, L<perlfunc>, L<perlunicode>, L<utf8>.
b3b6085d 1382
d396a558 1383=head1 REFERENCES
1384
2bbc8d55 1385L<http://anubis.dkuug.dk/i18n/charmaps>
d396a558 1386
2bbc8d55 1387L<http://www.unicode.org/>
d396a558 1388
2bbc8d55 1389L<http://www.unicode.org/unicode/reports/tr16/>
d396a558 1390
2bbc8d55 1391L<http://www.wps.com/texts/codes/>
51b5cecb 1392B<ASCII: American Standard Code for Information Infiltration> Tom Jennings,
1393September 1999.
1394
395f5a0c 1395B<The Unicode Standard, Version 3.0> The Unicode Consortium, Lisa Moore ed.,
51b5cecb 1396ISBN 0-201-61633-5, Addison Wesley Developers Press, February 2000.
1397
d396a558 1398B<CDRA: IBM - Character Data Representation Architecture -
1399Reference and Registry>, IBM SC09-2190-00, December 1996.
1400
1401"Demystifying Character Sets", Andrea Vine, Multilingual Computing
1402& Technology, B<#26 Vol. 10 Issue 4>, August/September 1999;
1403ISSN 1523-0309; Multilingual Computing Inc. Sandpoint ID, USA.
1404
1e054b24 1405B<Codes, Ciphers, and Other Cryptic and Clandestine Communication>
1406Fred B. Wrixon, ISBN 1-57912-040-7, Black Dog & Leventhal Publishers,
14071998.
1408
2bbc8d55 1409L<http://www.bobbemer.com/P-BIT.HTM>
395f5a0c 1410B<IBM - EBCDIC and the P-bit; The biggest Computer Goof Ever> Robert Bemer.
1411
1412=head1 HISTORY
1413
141415 April 2001: added UTF-8 and UTF-EBCDIC to main table, pvhp.
1415
d396a558 1416=head1 AUTHOR
1417
b3b6085d 1418Peter Prymmer pvhp@best.com wrote this in 1999 and 2000
d396a558 1419with CCSID 0819 and 0037 help from Chris Leach and
b3b6085d 1420AndrE<eacute> Pirard A.Pirard@ulg.ac.be as well as POSIX-BC
1421help from Thomas Dorner Thomas.Dorner@start.de.
1e054b24 1422Thanks also to Vickie Cooper, Philip Newton, William Raffloer, and
1423Joe Smith. Trademarks, registered trademarks, service marks and
1424registered service marks used in this document are the property of
1425their respective owners.
84f709e7 1426
1427
Unnamed repository; edit this file to name it for gitweb.