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1 | =head1 NAME |
2 | |
3 | perlebcdic - Considerations for running Perl on EBCDIC platforms |
4 | |
5 | =head1 DESCRIPTION |
6 | |
7 | An exploration of some of the issues facing Perl programmers |
8 | on EBCDIC based computers. We do not cover localization, |
9 | internationalization, or multi byte character set issues (yet). |
10 | |
11 | Portions that are still incomplete are marked with XXX. |
12 | |
13 | =head1 COMMON CHARACTER CODE SETS |
14 | |
15 | =head2 ASCII |
16 | |
17 | The American Standard Code for Information Interchange is a set of |
18 | integers running from 0 to 127 (decimal) that imply character |
19 | interpretation by the display and other system(s) of computers. |
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20 | The range 0..127 can be covered by setting the bits in a 7-bit binary |
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21 | digit, hence the set is sometimes referred to as a "7-bit ASCII". |
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22 | ASCII was described by the American National Standards Institute |
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23 | document ANSI X3.4-1986. It was also described by ISO 646:1991 |
24 | (with localization for currency symbols). The full ASCII set is |
25 | given in the table below as the first 128 elements. Languages that |
26 | can be written adequately with the characters in ASCII include |
27 | English, Hawaiian, Indonesian, Swahili and some Native American |
28 | languages. |
29 | |
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30 | There are many character sets that extend the range of integers |
31 | from 0..2**7-1 up to 2**8-1, or 8 bit bytes (octets if you prefer). |
32 | One common one is the ISO 8859-1 character set. |
33 | |
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34 | =head2 ISO 8859 |
35 | |
36 | The ISO 8859-$n are a collection of character code sets from the |
37 | International Organization for Standardization (ISO) each of which |
38 | adds characters to the ASCII set that are typically found in European |
39 | languages many of which are based on the Roman, or Latin, alphabet. |
40 | |
41 | =head2 Latin 1 (ISO 8859-1) |
42 | |
43 | A particular 8-bit extension to ASCII that includes grave and acute |
44 | accented Latin characters. Languages that can employ ISO 8859-1 |
45 | include all the languages covered by ASCII as well as Afrikaans, |
46 | Albanian, Basque, Catalan, Danish, Faroese, Finnish, Norwegian, |
47 | Portugese, Spanish, and Swedish. Dutch is covered albeit without |
48 | the ij ligature. French is covered too but without the oe ligature. |
49 | German can use ISO 8859-1 but must do so without German-style |
50 | quotation marks. This set is based on Western European extensions |
51 | to ASCII and is commonly encountered in world wide web work. |
52 | In IBM character code set identification terminology ISO 8859-1 is |
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53 | also known as CCSID 819 (or sometimes 0819 or even 00819). |
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54 | |
55 | =head2 EBCDIC |
56 | |
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57 | The Extended Binary Coded Decimal Interchange Code refers to a |
58 | large collection of slightly different single and multi byte |
59 | coded character sets that are different from ASCII or ISO 8859-1 |
60 | and typically run on host computers. The EBCDIC encodings derive |
61 | from 8 bit byte extensions of Hollerith punched card encodings. |
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62 | The layout on the cards was such that high bits were set for the |
63 | upper and lower case alphabet characters [a-z] and [A-Z], but there |
64 | were gaps within each latin alphabet range. |
65 | |
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66 | Some IBM EBCDIC character sets may be known by character code set |
67 | identification numbers (CCSID numbers) or code page numbers. Leading |
68 | zero digits in CCSID numbers within this document are insignificant. |
69 | E.g. CCSID 0037 may be referred to as 37 in places. |
70 | |
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71 | =head2 13 variant characters |
72 | |
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73 | Among IBM EBCDIC character code sets there are 13 characters that |
74 | are often mapped to different integer values. Those characters |
75 | are known as the 13 "variant" characters and are: |
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76 | |
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77 | \ [ ] { } ^ ~ ! # | $ @ ` |
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78 | |
79 | =head2 0037 |
80 | |
81 | Character code set ID 0037 is a mapping of the ASCII plus Latin-1 |
82 | characters (i.e. ISO 8859-1) to an EBCDIC set. 0037 is used |
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83 | in North American English locales on the OS/400 operating system |
84 | that runs on AS/400 computers. CCSID 37 differs from ISO 8859-1 |
85 | in 237 places, in other words they agree on only 19 code point values. |
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86 | |
87 | =head2 1047 |
88 | |
89 | Character code set ID 1047 is also a mapping of the ASCII plus |
90 | Latin-1 characters (i.e. ISO 8859-1) to an EBCDIC set. 1047 is |
91 | used under Unix System Services for OS/390, and OpenEdition for VM/ESA. |
92 | CCSID 1047 differs from CCSID 0037 in eight places. |
93 | |
94 | =head2 POSIX-BC |
95 | |
96 | The EBCDIC code page in use on Siemens' BS2000 system is distinct from |
97 | 1047 and 0037. It is identified below as the POSIX-BC set. |
98 | |
99 | =head1 SINGLE OCTET TABLES |
100 | |
101 | The following tables list the ASCII and Latin 1 ordered sets including |
102 | the subsets: C0 controls (0..31), ASCII graphics (32..7e), delete (7f), |
103 | C1 controls (80..9f), and Latin-1 (a.k.a. ISO 8859-1) (a0..ff). In the |
104 | table non-printing control character names as well as the Latin 1 |
105 | extensions to ASCII have been labelled with character names roughly |
106 | corresponding to I<The Unicode Standard, Version 2.0> albeit with |
107 | substitutions such as s/LATIN// and s/VULGAR// in all cases, |
108 | s/CAPITAL LETTER// in some cases, and s/SMALL LETTER ([A-Z])/\l$1/ |
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109 | in some other cases (the C<charnames> pragma names unfortunately do |
110 | not list explicit names for the C0 or C1 control characters). The |
111 | "names" of the C1 control set (128..159 in ISO 8859-1) listed here are |
112 | somewhat arbitrary. The differences between the 0037 and 1047 sets are |
113 | flagged with ***. The differences between the 1047 and POSIX-BC sets |
114 | are flagged with ###. All ord() numbers listed are decimal. If you |
115 | would rather see this table listing octal values then run the table |
116 | (that is, the pod version of this document since this recipe may not |
117 | work with a pod2_other_format translation) through: |
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118 | |
119 | =over 4 |
120 | |
121 | =item recipe 0 |
122 | |
123 | =back |
124 | |
125 | perl -ne 'if(/(.{33})(\d+)\s+(\d+)\s+(\d+)\s+(\d+)/)' \ |
126 | -e '{printf("%s%-9o%-9o%-9o%-9o\n",$1,$2,$3,$4,$5)}' perlebcdic.pod |
127 | |
128 | If you would rather see this table listing hexadecimal values then |
129 | run the table through: |
130 | |
131 | =over 4 |
132 | |
133 | =item recipe 1 |
134 | |
135 | =back |
136 | |
137 | perl -ne 'if(/(.{33})(\d+)\s+(\d+)\s+(\d+)\s+(\d+)/)' \ |
138 | -e '{printf("%s%-9X%-9X%-9X%-9X\n",$1,$2,$3,$4,$5)}' perlebcdic.pod |
139 | |
140 | |
141 | 8859-1 |
142 | chr 0819 0037 1047 POSIX-BC |
143 | ---------------------------------------------------------------- |
144 | <NULL> 0 0 0 0 |
145 | <START OF HEADING> 1 1 1 1 |
146 | <START OF TEXT> 2 2 2 2 |
147 | <END OF TEXT> 3 3 3 3 |
148 | <END OF TRANSMISSION> 4 55 55 55 |
149 | <ENQUIRY> 5 45 45 45 |
150 | <ACKNOWLEDGE> 6 46 46 46 |
151 | <BELL> 7 47 47 47 |
152 | <BACKSPACE> 8 22 22 22 |
153 | <HORIZONTAL TABULATION> 9 5 5 5 |
154 | <LINE FEED> 10 37 21 21 *** |
155 | <VERTICAL TABULATION> 11 11 11 11 |
156 | <FORM FEED> 12 12 12 12 |
157 | <CARRIAGE RETURN> 13 13 13 13 |
158 | <SHIFT OUT> 14 14 14 14 |
159 | <SHIFT IN> 15 15 15 15 |
160 | <DATA LINK ESCAPE> 16 16 16 16 |
161 | <DEVICE CONTROL ONE> 17 17 17 17 |
162 | <DEVICE CONTROL TWO> 18 18 18 18 |
163 | <DEVICE CONTROL THREE> 19 19 19 19 |
164 | <DEVICE CONTROL FOUR> 20 60 60 60 |
165 | <NEGATIVE ACKNOWLEDGE> 21 61 61 61 |
166 | <SYNCHRONOUS IDLE> 22 50 50 50 |
167 | <END OF TRANSMISSION BLOCK> 23 38 38 38 |
168 | <CANCEL> 24 24 24 24 |
169 | <END OF MEDIUM> 25 25 25 25 |
170 | <SUBSTITUTE> 26 63 63 63 |
171 | <ESCAPE> 27 39 39 39 |
172 | <FILE SEPARATOR> 28 28 28 28 |
173 | <GROUP SEPARATOR> 29 29 29 29 |
174 | <RECORD SEPARATOR> 30 30 30 30 |
175 | <UNIT SEPARATOR> 31 31 31 31 |
176 | <SPACE> 32 64 64 64 |
177 | ! 33 90 90 90 |
178 | " 34 127 127 127 |
179 | # 35 123 123 123 |
180 | $ 36 91 91 91 |
181 | % 37 108 108 108 |
182 | & 38 80 80 80 |
183 | ' 39 125 125 125 |
184 | ( 40 77 77 77 |
185 | ) 41 93 93 93 |
186 | * 42 92 92 92 |
187 | + 43 78 78 78 |
188 | , 44 107 107 107 |
189 | - 45 96 96 96 |
190 | . 46 75 75 75 |
191 | / 47 97 97 97 |
192 | 0 48 240 240 240 |
193 | 1 49 241 241 241 |
194 | 2 50 242 242 242 |
195 | 3 51 243 243 243 |
196 | 4 52 244 244 244 |
197 | 5 53 245 245 245 |
198 | 6 54 246 246 246 |
199 | 7 55 247 247 247 |
200 | 8 56 248 248 248 |
201 | 9 57 249 249 249 |
202 | : 58 122 122 122 |
203 | ; 59 94 94 94 |
204 | < 60 76 76 76 |
205 | = 61 126 126 126 |
206 | > 62 110 110 110 |
207 | ? 63 111 111 111 |
208 | @ 64 124 124 124 |
209 | A 65 193 193 193 |
210 | B 66 194 194 194 |
211 | C 67 195 195 195 |
212 | D 68 196 196 196 |
213 | E 69 197 197 197 |
214 | F 70 198 198 198 |
215 | G 71 199 199 199 |
216 | H 72 200 200 200 |
217 | I 73 201 201 201 |
218 | J 74 209 209 209 |
219 | K 75 210 210 210 |
220 | L 76 211 211 211 |
221 | M 77 212 212 212 |
222 | N 78 213 213 213 |
223 | O 79 214 214 214 |
224 | P 80 215 215 215 |
225 | Q 81 216 216 216 |
226 | R 82 217 217 217 |
227 | S 83 226 226 226 |
228 | T 84 227 227 227 |
229 | U 85 228 228 228 |
230 | V 86 229 229 229 |
231 | W 87 230 230 230 |
232 | X 88 231 231 231 |
233 | Y 89 232 232 232 |
234 | Z 90 233 233 233 |
235 | [ 91 186 173 187 *** ### |
236 | \ 92 224 224 188 ### |
237 | ] 93 187 189 189 *** |
238 | ^ 94 176 95 106 *** ### |
239 | _ 95 109 109 109 |
240 | ` 96 121 121 74 ### |
241 | a 97 129 129 129 |
242 | b 98 130 130 130 |
243 | c 99 131 131 131 |
244 | d 100 132 132 132 |
245 | e 101 133 133 133 |
246 | f 102 134 134 134 |
247 | g 103 135 135 135 |
248 | h 104 136 136 136 |
249 | i 105 137 137 137 |
250 | j 106 145 145 145 |
251 | k 107 146 146 146 |
252 | l 108 147 147 147 |
253 | m 109 148 148 148 |
254 | n 110 149 149 149 |
255 | o 111 150 150 150 |
256 | p 112 151 151 151 |
257 | q 113 152 152 152 |
258 | r 114 153 153 153 |
259 | s 115 162 162 162 |
260 | t 116 163 163 163 |
261 | u 117 164 164 164 |
262 | v 118 165 165 165 |
263 | w 119 166 166 166 |
264 | x 120 167 167 167 |
265 | y 121 168 168 168 |
266 | z 122 169 169 169 |
267 | { 123 192 192 251 ### |
268 | | 124 79 79 79 |
269 | } 125 208 208 253 ### |
270 | ~ 126 161 161 255 ### |
271 | <DELETE> 127 7 7 7 |
272 | <C1 0> 128 32 32 32 |
273 | <C1 1> 129 33 33 33 |
274 | <C1 2> 130 34 34 34 |
275 | <C1 3> 131 35 35 35 |
276 | <C1 4> 132 36 36 36 |
277 | <C1 5> 133 21 37 37 *** |
278 | <C1 6> 134 6 6 6 |
279 | <C1 7> 135 23 23 23 |
280 | <C1 8> 136 40 40 40 |
281 | <C1 9> 137 41 41 41 |
282 | <C1 10> 138 42 42 42 |
283 | <C1 11> 139 43 43 43 |
284 | <C1 12> 140 44 44 44 |
285 | <C1 13> 141 9 9 9 |
286 | <C1 14> 142 10 10 10 |
287 | <C1 15> 143 27 27 27 |
288 | <C1 16> 144 48 48 48 |
289 | <C1 17> 145 49 49 49 |
290 | <C1 18> 146 26 26 26 |
291 | <C1 19> 147 51 51 51 |
292 | <C1 20> 148 52 52 52 |
293 | <C1 21> 149 53 53 53 |
294 | <C1 22> 150 54 54 54 |
295 | <C1 23> 151 8 8 8 |
296 | <C1 24> 152 56 56 56 |
297 | <C1 25> 153 57 57 57 |
298 | <C1 26> 154 58 58 58 |
299 | <C1 27> 155 59 59 59 |
300 | <C1 28> 156 4 4 4 |
301 | <C1 29> 157 20 20 20 |
302 | <C1 30> 158 62 62 62 |
303 | <C1 31> 159 255 255 95 ### |
304 | <NON-BREAKING SPACE> 160 65 65 65 |
305 | <INVERTED EXCLAMATION MARK> 161 170 170 170 |
306 | <CENT SIGN> 162 74 74 176 ### |
307 | <POUND SIGN> 163 177 177 177 |
308 | <CURRENCY SIGN> 164 159 159 159 |
309 | <YEN SIGN> 165 178 178 178 |
310 | <BROKEN BAR> 166 106 106 208 ### |
311 | <SECTION SIGN> 167 181 181 181 |
312 | <DIAERESIS> 168 189 187 121 *** ### |
313 | <COPYRIGHT SIGN> 169 180 180 180 |
314 | <FEMININE ORDINAL INDICATOR> 170 154 154 154 |
315 | <LEFT POINTING GUILLEMET> 171 138 138 138 |
316 | <NOT SIGN> 172 95 176 186 *** ### |
317 | <SOFT HYPHEN> 173 202 202 202 |
318 | <REGISTERED TRADE MARK SIGN> 174 175 175 175 |
319 | <MACRON> 175 188 188 161 ### |
320 | <DEGREE SIGN> 176 144 144 144 |
321 | <PLUS-OR-MINUS SIGN> 177 143 143 143 |
322 | <SUPERSCRIPT TWO> 178 234 234 234 |
323 | <SUPERSCRIPT THREE> 179 250 250 250 |
324 | <ACUTE ACCENT> 180 190 190 190 |
325 | <MICRO SIGN> 181 160 160 160 |
326 | <PARAGRAPH SIGN> 182 182 182 182 |
327 | <MIDDLE DOT> 183 179 179 179 |
328 | <CEDILLA> 184 157 157 157 |
329 | <SUPERSCRIPT ONE> 185 218 218 218 |
330 | <MASC. ORDINAL INDICATOR> 186 155 155 155 |
331 | <RIGHT POINTING GUILLEMET> 187 139 139 139 |
332 | <FRACTION ONE QUARTER> 188 183 183 183 |
333 | <FRACTION ONE HALF> 189 184 184 184 |
334 | <FRACTION THREE QUARTERS> 190 185 185 185 |
335 | <INVERTED QUESTION MARK> 191 171 171 171 |
336 | <A WITH GRAVE> 192 100 100 100 |
337 | <A WITH ACUTE> 193 101 101 101 |
338 | <A WITH CIRCUMFLEX> 194 98 98 98 |
339 | <A WITH TILDE> 195 102 102 102 |
340 | <A WITH DIAERESIS> 196 99 99 99 |
341 | <A WITH RING ABOVE> 197 103 103 103 |
342 | <CAPITAL LIGATURE AE> 198 158 158 158 |
343 | <C WITH CEDILLA> 199 104 104 104 |
344 | <E WITH GRAVE> 200 116 116 116 |
345 | <E WITH ACUTE> 201 113 113 113 |
346 | <E WITH CIRCUMFLEX> 202 114 114 114 |
347 | <E WITH DIAERESIS> 203 115 115 115 |
348 | <I WITH GRAVE> 204 120 120 120 |
349 | <I WITH ACUTE> 205 117 117 117 |
350 | <I WITH CIRCUMFLEX> 206 118 118 118 |
351 | <I WITH DIAERESIS> 207 119 119 119 |
352 | <CAPITAL LETTER ETH> 208 172 172 172 |
353 | <N WITH TILDE> 209 105 105 105 |
354 | <O WITH GRAVE> 210 237 237 237 |
355 | <O WITH ACUTE> 211 238 238 238 |
356 | <O WITH CIRCUMFLEX> 212 235 235 235 |
357 | <O WITH TILDE> 213 239 239 239 |
358 | <O WITH DIAERESIS> 214 236 236 236 |
359 | <MULTIPLICATION SIGN> 215 191 191 191 |
360 | <O WITH STROKE> 216 128 128 128 |
361 | <U WITH GRAVE> 217 253 253 224 ### |
362 | <U WITH ACUTE> 218 254 254 254 |
363 | <U WITH CIRCUMFLEX> 219 251 251 221 ### |
364 | <U WITH DIAERESIS> 220 252 252 252 |
365 | <Y WITH ACUTE> 221 173 186 173 *** ### |
366 | <CAPITAL LETTER THORN> 222 174 174 174 |
367 | <SMALL LETTER SHARP S> 223 89 89 89 |
368 | <a WITH GRAVE> 224 68 68 68 |
369 | <a WITH ACUTE> 225 69 69 69 |
370 | <a WITH CIRCUMFLEX> 226 66 66 66 |
371 | <a WITH TILDE> 227 70 70 70 |
372 | <a WITH DIAERESIS> 228 67 67 67 |
373 | <a WITH RING ABOVE> 229 71 71 71 |
374 | <SMALL LIGATURE ae> 230 156 156 156 |
375 | <c WITH CEDILLA> 231 72 72 72 |
376 | <e WITH GRAVE> 232 84 84 84 |
377 | <e WITH ACUTE> 233 81 81 81 |
378 | <e WITH CIRCUMFLEX> 234 82 82 82 |
379 | <e WITH DIAERESIS> 235 83 83 83 |
380 | <i WITH GRAVE> 236 88 88 88 |
381 | <i WITH ACUTE> 237 85 85 85 |
382 | <i WITH CIRCUMFLEX> 238 86 86 86 |
383 | <i WITH DIAERESIS> 239 87 87 87 |
384 | <SMALL LETTER eth> 240 140 140 140 |
385 | <n WITH TILDE> 241 73 73 73 |
386 | <o WITH GRAVE> 242 205 205 205 |
387 | <o WITH ACUTE> 243 206 206 206 |
388 | <o WITH CIRCUMFLEX> 244 203 203 203 |
389 | <o WITH TILDE> 245 207 207 207 |
390 | <o WITH DIAERESIS> 246 204 204 204 |
391 | <DIVISION SIGN> 247 225 225 225 |
392 | <o WITH STROKE> 248 112 112 112 |
393 | <u WITH GRAVE> 249 221 221 192 ### |
394 | <u WITH ACUTE> 250 222 222 222 |
395 | <u WITH CIRCUMFLEX> 251 219 219 219 |
396 | <u WITH DIAERESIS> 252 220 220 220 |
397 | <y WITH ACUTE> 253 141 141 141 |
398 | <SMALL LETTER thorn> 254 142 142 142 |
399 | <y WITH DIAERESIS> 255 223 223 223 |
400 | |
401 | If you would rather see the above table in CCSID 0037 order rather than |
402 | ASCII + Latin-1 order then run the table through: |
403 | |
404 | =over 4 |
405 | |
406 | =item recipe 2 |
407 | |
408 | =back |
409 | |
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410 | 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}/)'\ |
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411 | -e '{push(@l,$_)}' \ |
412 | -e 'END{print map{$_->[0]}' \ |
413 | -e ' sort{$a->[1] <=> $b->[1]}' \ |
414 | -e ' map{[$_,substr($_,42,3)]}@l;}' perlebcdic.pod |
415 | |
416 | If you would rather see it in CCSID 1047 order then change the digit |
417 | 42 in the last line to 51, like this: |
418 | |
419 | =over 4 |
420 | |
421 | =item recipe 3 |
422 | |
423 | =back |
424 | |
51b5cecb |
425 | perl -ne 'if(/.{33}\d{1,3}\s{6,8}\d{1,3}\s{6,8}\d{1,3}\s{6,8}\d{1,3}/)'\ |
d396a558 |
426 | -e '{push(@l,$_)}' \ |
427 | -e 'END{print map{$_->[0]}' \ |
428 | -e ' sort{$a->[1] <=> $b->[1]}' \ |
429 | -e ' map{[$_,substr($_,51,3)]}@l;}' perlebcdic.pod |
430 | |
431 | If you would rather see it in POSIX-BC order then change the digit |
432 | 51 in the last line to 60, like this: |
433 | |
434 | =over 4 |
435 | |
436 | =item recipe 4 |
437 | |
438 | =back |
439 | |
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440 | perl -ne 'if(/.{33}\d{1,3}\s{6,8}\d{1,3}\s{6,8}\d{1,3}\s{6,8}\d{1,3}/)'\ |
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441 | -e '{push(@l,$_)}' \ |
442 | -e 'END{print map{$_->[0]}' \ |
443 | -e ' sort{$a->[1] <=> $b->[1]}' \ |
444 | -e ' map{[$_,substr($_,60,3)]}@l;}' perlebcdic.pod |
445 | |
446 | |
447 | =head1 IDENTIFYING CHARACTER CODE SETS |
448 | |
449 | To determine the character set you are running under from perl one |
450 | could use the return value of ord() or chr() to test one or more |
451 | character values. For example: |
452 | |
453 | $is_ascii = "A" eq chr(65); |
454 | $is_ebcdic = "A" eq chr(193); |
455 | |
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456 | Also, "\t" is a C<HORIZONTAL TABULATION> character so that: |
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457 | |
458 | $is_ascii = ord("\t") == 9; |
459 | $is_ebcdic = ord("\t") == 5; |
460 | |
461 | To distinguish EBCDIC code pages try looking at one or more of |
462 | the characters that differ between them. For example: |
463 | |
464 | $is_ebcdic_37 = "\n" eq chr(37); |
465 | $is_ebcdic_1047 = "\n" eq chr(21); |
466 | |
467 | Or better still choose a character that is uniquely encoded in any |
468 | of the code sets, e.g.: |
469 | |
470 | $is_ascii = ord('[') == 91; |
471 | $is_ebcdic_37 = ord('[') == 186; |
472 | $is_ebcdic_1047 = ord('[') == 173; |
473 | $is_ebcdic_POSIX_BC = ord('[') == 187; |
474 | |
475 | However, it would be unwise to write tests such as: |
476 | |
477 | $is_ascii = "\r" ne chr(13); # WRONG |
478 | $is_ascii = "\n" ne chr(10); # ILL ADVISED |
479 | |
480 | Obviously the first of these will fail to distinguish most ASCII machines |
481 | from either a CCSID 0037, a 1047, or a POSIX-BC EBCDIC machine since "\r" eq |
482 | chr(13) under all of those coded character sets. But note too that |
483 | because "\n" is chr(13) and "\r" is chr(10) on the MacIntosh (which is an |
484 | ASCII machine) the second C<$is_ascii> test will lead to trouble there. |
485 | |
486 | To determine whether or not perl was built under an EBCDIC |
487 | code page you can use the Config module like so: |
488 | |
489 | use Config; |
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490 | $is_ebcdic = $Config{'ebcdic'} eq 'define'; |
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491 | |
492 | =head1 CONVERSIONS |
493 | |
1e054b24 |
494 | =head2 tr/// |
495 | |
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496 | In order to convert a string of characters from one character set to |
497 | another a simple list of numbers, such as in the right columns in the |
498 | above table, along with perl's tr/// operator is all that is needed. |
499 | The data in the table are in ASCII order hence the EBCDIC columns |
500 | provide easy to use ASCII to EBCDIC operations that are also easily |
501 | reversed. |
502 | |
503 | For example, to convert ASCII to code page 037 take the output of the second |
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504 | column from the output of recipe 0 (modified to add \\ characters) and use |
505 | it in tr/// like so: |
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506 | |
507 | $cp_037 = |
508 | '\000\001\002\003\234\011\206\177\227\215\216\013\014\015\016\017' . |
509 | '\020\021\022\023\235\205\010\207\030\031\222\217\034\035\036\037' . |
510 | '\200\201\202\203\204\012\027\033\210\211\212\213\214\005\006\007' . |
511 | '\220\221\026\223\224\225\226\004\230\231\232\233\024\025\236\032' . |
512 | '\040\240\342\344\340\341\343\345\347\361\242\056\074\050\053\174' . |
513 | '\046\351\352\353\350\355\356\357\354\337\041\044\052\051\073\254' . |
514 | '\055\057\302\304\300\301\303\305\307\321\246\054\045\137\076\077' . |
515 | '\370\311\312\313\310\315\316\317\314\140\072\043\100\047\075\042' . |
516 | '\330\141\142\143\144\145\146\147\150\151\253\273\360\375\376\261' . |
517 | '\260\152\153\154\155\156\157\160\161\162\252\272\346\270\306\244' . |
518 | '\265\176\163\164\165\166\167\170\171\172\241\277\320\335\336\256' . |
519 | '\136\243\245\267\251\247\266\274\275\276\133\135\257\250\264\327' . |
520 | '\173\101\102\103\104\105\106\107\110\111\255\364\366\362\363\365' . |
521 | '\175\112\113\114\115\116\117\120\121\122\271\373\374\371\372\377' . |
522 | '\134\367\123\124\125\126\127\130\131\132\262\324\326\322\323\325' . |
523 | '\060\061\062\063\064\065\066\067\070\071\263\333\334\331\332\237' ; |
524 | |
525 | my $ebcdic_string = $ascii_string; |
1e054b24 |
526 | eval '$ebcdic_string =~ tr/\000-\377/' . $cp_037 . '/'; |
d396a558 |
527 | |
d5d9880c |
528 | To convert from EBCDIC 037 to ASCII just reverse the order of the tr/// |
d396a558 |
529 | arguments like so: |
530 | |
531 | my $ascii_string = $ebcdic_string; |
d5d9880c |
532 | eval '$ascii_string = tr/' . $cp_037 . '/\000-\377/'; |
533 | |
534 | Similarly one could take the output of the third column from recipe 0 to |
535 | obtain a C<$cp_1047> table. The fourth column of the output from recipe |
536 | 0 could provide a C<$cp_posix_bc> table suitable for transcoding as well. |
1e054b24 |
537 | |
538 | =head2 iconv |
d396a558 |
539 | |
d5d9880c |
540 | XPG operability often implies the presence of an I<iconv> utility |
d396a558 |
541 | available from the shell or from the C library. Consult your system's |
542 | documentation for information on iconv. |
543 | |
544 | On OS/390 see the iconv(1) man page. One way to invoke the iconv |
545 | shell utility from within perl would be to: |
546 | |
51b5cecb |
547 | # OS/390 example |
d396a558 |
548 | $ascii_data = `echo '$ebcdic_data'| iconv -f IBM-1047 -t ISO8859-1` |
549 | |
550 | or the inverse map: |
551 | |
51b5cecb |
552 | # OS/390 example |
d396a558 |
553 | $ebcdic_data = `echo '$ascii_data'| iconv -f ISO8859-1 -t IBM-1047` |
554 | |
d396a558 |
555 | For other perl based conversion options see the Convert::* modules on CPAN. |
556 | |
1e054b24 |
557 | =head2 C RTL |
558 | |
559 | The OS/390 C run time library provides _atoe() and _etoa() functions. |
560 | |
d396a558 |
561 | =head1 OPERATOR DIFFERENCES |
562 | |
563 | The C<..> range operator treats certain character ranges with |
564 | care on EBCDIC machines. For example the following array |
565 | will have twenty six elements on either an EBCDIC machine |
566 | or an ASCII machine: |
567 | |
568 | @alphabet = ('A'..'Z'); # $#alphabet == 25 |
569 | |
570 | The bitwise operators such as & ^ | may return different results |
571 | when operating on string or character data in a perl program running |
572 | on an EBCDIC machine than when run on an ASCII machine. Here is |
573 | an example adapted from the one in L<perlop>: |
574 | |
575 | # EBCDIC-based examples |
576 | print "j p \n" ^ " a h"; # prints "JAPH\n" |
577 | print "JA" | " ph\n"; # prints "japh\n" |
578 | print "JAPH\nJunk" & "\277\277\277\277\277"; # prints "japh\n"; |
579 | print 'p N$' ^ " E<H\n"; # prints "Perl\n"; |
580 | |
581 | An interesting property of the 32 C0 control characters |
582 | in the ASCII table is that they can "literally" be constructed |
51b5cecb |
583 | as control characters in perl, e.g. C<(chr(0) eq "\c@")> |
584 | C<(chr(1) eq "\cA")>, and so on. Perl on EBCDIC machines has been |
585 | ported to take "\c@" to chr(0) and "\cA" to chr(1) as well, but the |
d396a558 |
586 | thirty three characters that result depend on which code page you are |
587 | using. The table below uses the character names from the previous table |
51b5cecb |
588 | but with substitutions such as s/START OF/S.O./; s/END OF /E.O./; |
d396a558 |
589 | s/TRANSMISSION/TRANS./; s/TABULATION/TAB./; s/VERTICAL/VERT./; |
590 | s/HORIZONTAL/HORIZ./; s/DEVICE CONTROL/D.C./; s/SEPARATOR/SEP./; |
591 | s/NEGATIVE ACKNOWLEDGE/NEG. ACK./;. The POSIX-BC and 1047 sets are |
592 | identical throughout this range and differ from the 0037 set at only |
51b5cecb |
593 | one spot (21 decimal). Note that the C<LINE FEED> character |
594 | may be generated by "\cJ" on ASCII machines but by "\cU" on 1047 or POSIX-BC |
595 | machines and cannot be generated as a C<"\c.letter."> control character on |
596 | 0037 machines. Note also that "\c\\" maps to two characters |
d396a558 |
597 | not one. |
598 | |
599 | chr ord 8859-1 0037 1047 && POSIX-BC |
600 | ------------------------------------------------------------------------ |
601 | "\c?" 127 <DELETE> " " ***>< |
602 | "\c@" 0 <NULL> <NULL> <NULL> ***>< |
603 | "\cA" 1 <S.O. HEADING> <S.O. HEADING> <S.O. HEADING> |
604 | "\cB" 2 <S.O. TEXT> <S.O. TEXT> <S.O. TEXT> |
605 | "\cC" 3 <E.O. TEXT> <E.O. TEXT> <E.O. TEXT> |
606 | "\cD" 4 <E.O. TRANS.> <C1 28> <C1 28> |
607 | "\cE" 5 <ENQUIRY> <HORIZ. TAB.> <HORIZ. TAB.> |
608 | "\cF" 6 <ACKNOWLEDGE> <C1 6> <C1 6> |
609 | "\cG" 7 <BELL> <DELETE> <DELETE> |
610 | "\cH" 8 <BACKSPACE> <C1 23> <C1 23> |
611 | "\cI" 9 <HORIZ. TAB.> <C1 13> <C1 13> |
612 | "\cJ" 10 <LINE FEED> <C1 14> <C1 14> |
613 | "\cK" 11 <VERT. TAB.> <VERT. TAB.> <VERT. TAB.> |
614 | "\cL" 12 <FORM FEED> <FORM FEED> <FORM FEED> |
615 | "\cM" 13 <CARRIAGE RETURN> <CARRIAGE RETURN> <CARRIAGE RETURN> |
616 | "\cN" 14 <SHIFT OUT> <SHIFT OUT> <SHIFT OUT> |
617 | "\cO" 15 <SHIFT IN> <SHIFT IN> <SHIFT IN> |
618 | "\cP" 16 <DATA LINK ESCAPE> <DATA LINK ESCAPE> <DATA LINK ESCAPE> |
619 | "\cQ" 17 <D.C. ONE> <D.C. ONE> <D.C. ONE> |
620 | "\cR" 18 <D.C. TWO> <D.C. TWO> <D.C. TWO> |
621 | "\cS" 19 <D.C. THREE> <D.C. THREE> <D.C. THREE> |
622 | "\cT" 20 <D.C. FOUR> <C1 29> <C1 29> |
623 | "\cU" 21 <NEG. ACK.> <C1 5> <LINE FEED> *** |
624 | "\cV" 22 <SYNCHRONOUS IDLE> <BACKSPACE> <BACKSPACE> |
625 | "\cW" 23 <E.O. TRANS. BLOCK> <C1 7> <C1 7> |
626 | "\cX" 24 <CANCEL> <CANCEL> <CANCEL> |
627 | "\cY" 25 <E.O. MEDIUM> <E.O. MEDIUM> <E.O. MEDIUM> |
628 | "\cZ" 26 <SUBSTITUTE> <C1 18> <C1 18> |
629 | "\c[" 27 <ESCAPE> <C1 15> <C1 15> |
630 | "\c\\" 28 <FILE SEP.>\ <FILE SEP.>\ <FILE SEP.>\ |
631 | "\c]" 29 <GROUP SEP.> <GROUP SEP.> <GROUP SEP.> |
632 | "\c^" 30 <RECORD SEP.> <RECORD SEP.> <RECORD SEP.> ***>< |
633 | "\c_" 31 <UNIT SEP.> <UNIT SEP.> <UNIT SEP.> ***>< |
634 | |
635 | |
636 | =head1 FUNCTION DIFFERENCES |
637 | |
638 | =over 8 |
639 | |
640 | =item chr() |
641 | |
642 | chr() must be given an EBCDIC code number argument to yield a desired |
643 | character return value on an EBCDIC machine. For example: |
644 | |
645 | $CAPITAL_LETTER_A = chr(193); |
646 | |
647 | =item ord() |
648 | |
649 | ord() will return EBCDIC code number values on an EBCDIC machine. |
650 | For example: |
651 | |
652 | $the_number_193 = ord("A"); |
653 | |
654 | =item pack() |
655 | |
656 | The c and C templates for pack() are dependent upon character set |
657 | encoding. Examples of usage on EBCDIC include: |
658 | |
659 | $foo = pack("CCCC",193,194,195,196); |
660 | # $foo eq "ABCD" |
661 | $foo = pack("C4",193,194,195,196); |
662 | # same thing |
663 | |
664 | $foo = pack("ccxxcc",193,194,195,196); |
665 | # $foo eq "AB\0\0CD" |
666 | |
667 | =item print() |
668 | |
669 | One must be careful with scalars and strings that are passed to |
670 | print that contain ASCII encodings. One common place |
671 | for this to occur is in the output of the MIME type header for |
672 | CGI script writing. For example, many perl programming guides |
673 | recommend something similar to: |
674 | |
675 | print "Content-type:\ttext/html\015\012\015\012"; |
676 | # this may be wrong on EBCDIC |
677 | |
678 | Under the IBM OS/390 USS Web Server for example you should instead |
679 | write that as: |
680 | |
681 | print "Content-type:\ttext/html\r\n\r\n"; # OK for DGW et alia |
682 | |
683 | That is because the translation from EBCDIC to ASCII is done |
684 | by the web server in this case (such code will not be appropriate for |
685 | the Macintosh however). Consult your web server's documentation for |
686 | further details. |
687 | |
688 | =item printf() |
689 | |
690 | The formats that can convert characters to numbers and vice versa |
691 | will be different from their ASCII counterparts when executed |
692 | on an EBCDIC machine. Examples include: |
693 | |
694 | printf("%c%c%c",193,194,195); # prints ABC |
695 | |
696 | =item sort() |
697 | |
698 | EBCDIC sort results may differ from ASCII sort results especially for |
699 | mixed case strings. This is discussed in more detail below. |
700 | |
701 | =item sprintf() |
702 | |
703 | See the discussion of printf() above. An example of the use |
704 | of sprintf would be: |
705 | |
706 | $CAPITAL_LETTER_A = sprintf("%c",193); |
707 | |
708 | =item unpack() |
709 | |
710 | See the discussion of pack() above. |
711 | |
712 | =back |
713 | |
714 | =head1 REGULAR EXPRESSION DIFFERENCES |
715 | |
716 | As of perl 5.005_03 the letter range regular expression such as |
717 | [A-Z] and [a-z] have been especially coded to not pick up gap |
b3b6085d |
718 | characters. For example, characters such as E<ocirc> C<o WITH CIRCUMFLEX> |
719 | that lie between I and J would not be matched by the |
51b5cecb |
720 | regular expression range C</[H-K]/>. |
721 | |
722 | If you do want to match the alphabet gap characters in a single octet |
d396a558 |
723 | regular expression try matching the hex or octal code such |
724 | as C</\313/> on EBCDIC or C</\364/> on ASCII machines to |
51b5cecb |
725 | have your regular expression match C<o WITH CIRCUMFLEX>. |
d396a558 |
726 | |
51b5cecb |
727 | Another construct to be wary of is the inappropriate use of hex or |
d396a558 |
728 | octal constants in regular expressions. Consider the following |
729 | set of subs: |
730 | |
731 | sub is_c0 { |
732 | my $char = substr(shift,0,1); |
733 | $char =~ /[\000-\037]/; |
734 | } |
735 | |
736 | sub is_print_ascii { |
737 | my $char = substr(shift,0,1); |
738 | $char =~ /[\040-\176]/; |
739 | } |
740 | |
741 | sub is_delete { |
742 | my $char = substr(shift,0,1); |
743 | $char eq "\177"; |
744 | } |
745 | |
746 | sub is_c1 { |
747 | my $char = substr(shift,0,1); |
748 | $char =~ /[\200-\237]/; |
749 | } |
750 | |
751 | sub is_latin_1 { |
752 | my $char = substr(shift,0,1); |
753 | $char =~ /[\240-\377]/; |
754 | } |
755 | |
51b5cecb |
756 | The above would be adequate if the concern was only with numeric code points. |
757 | However, the concern may be with characters rather than code points |
758 | and on an EBCDIC machine it may be desirable for constructs such as |
d396a558 |
759 | C<if (is_print_ascii("A")) {print "A is a printable character\n";}> to print |
760 | out the expected message. One way to represent the above collection |
761 | of character classification subs that is capable of working across the |
762 | four coded character sets discussed in this document is as follows: |
763 | |
764 | sub Is_c0 { |
765 | my $char = substr(shift,0,1); |
766 | if (ord('^')==94) { # ascii |
767 | return $char =~ /[\000-\037]/; |
768 | } |
769 | if (ord('^')==176) { # 37 |
770 | return $char =~ /[\000-\003\067\055-\057\026\005\045\013-\023\074\075\062\046\030\031\077\047\034-\037]/; |
771 | } |
772 | if (ord('^')==95 || ord('^')==106) { # 1047 || posix-bc |
773 | return $char =~ /[\000-\003\067\055-\057\026\005\025\013-\023\074\075\062\046\030\031\077\047\034-\037]/; |
774 | } |
775 | } |
776 | |
777 | sub Is_print_ascii { |
778 | my $char = substr(shift,0,1); |
779 | $char =~ /[ !"\#\$%&'()*+,\-.\/0-9:;<=>?\@A-Z[\\\]^_`a-z{|}~]/; |
780 | } |
781 | |
782 | sub Is_delete { |
783 | my $char = substr(shift,0,1); |
784 | if (ord('^')==94) { # ascii |
785 | return $char eq "\177"; |
786 | } |
787 | else { # ebcdic |
788 | return $char eq "\007"; |
789 | } |
790 | } |
791 | |
792 | sub Is_c1 { |
793 | my $char = substr(shift,0,1); |
794 | if (ord('^')==94) { # ascii |
795 | return $char =~ /[\200-\237]/; |
796 | } |
797 | if (ord('^')==176) { # 37 |
798 | return $char =~ /[\040-\044\025\006\027\050-\054\011\012\033\060\061\032\063-\066\010\070-\073\040\024\076\377]/; |
799 | } |
800 | if (ord('^')==95) { # 1047 |
801 | return $char =~ /[\040-\045\006\027\050-\054\011\012\033\060\061\032\063-\066\010\070-\073\040\024\076\377]/; |
802 | } |
803 | if (ord('^')==106) { # posix-bc |
804 | return $char =~ |
805 | /[\040-\045\006\027\050-\054\011\012\033\060\061\032\063-\066\010\070-\073\040\024\076\137]/; |
806 | } |
807 | } |
808 | |
809 | sub Is_latin_1 { |
810 | my $char = substr(shift,0,1); |
811 | if (ord('^')==94) { # ascii |
812 | return $char =~ /[\240-\377]/; |
813 | } |
814 | if (ord('^')==176) { # 37 |
815 | return $char =~ |
816 | /[\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]/; |
817 | } |
818 | if (ord('^')==95) { # 1047 |
819 | return $char =~ |
820 | /[\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]/; |
821 | } |
822 | if (ord('^')==106) { # posix-bc |
823 | return $char =~ |
824 | /[\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]/; |
825 | } |
826 | } |
827 | |
828 | Note however that only the C<Is_ascii_print()> sub is really independent |
829 | of coded character set. Another way to write C<Is_latin_1()> would be |
830 | to use the characters in the range explicitly: |
831 | |
832 | sub Is_latin_1 { |
833 | my $char = substr(shift,0,1); |
834 | $char =~ /[ ¡¢£¤¥¦§¨©ª«¬®¯°±²³´µ¶·¸¹º»¼½¾¿ÀÁÂÃÄÅÆÇÈÉÊËÌÍÎÏÐÑÒÓÔÕÖ×ØÙÚÛÜÝÞßàáâãäåæçèéêëìíîïðñòóôõö÷øùúûüýþÿ]/; |
835 | } |
836 | |
837 | Although that form may run into trouble in network transit (due to the |
838 | presence of 8 bit characters) or on non ISO-Latin character sets. |
d396a558 |
839 | |
840 | =head1 SOCKETS |
841 | |
842 | Most socket programming assumes ASCII character encodings in network |
843 | byte order. Exceptions can include CGI script writing under a |
844 | host web server where the server may take care of translation for you. |
845 | Most host web servers convert EBCDIC data to ISO-8859-1 or Unicode on |
846 | output. |
847 | |
848 | =head1 SORTING |
849 | |
850 | One big difference between ASCII based character sets and EBCDIC ones |
851 | are the relative positions of upper and lower case letters and the |
852 | letters compared to the digits. If sorted on an ASCII based machine the |
853 | two letter abbreviation for a physician comes before the two letter |
854 | for drive, that is: |
855 | |
51b5cecb |
856 | @sorted = sort(qw(Dr. dr.)); # @sorted holds ('Dr.','dr.') on ASCII, |
857 | # but ('dr.','Dr.') on EBCDIC |
d396a558 |
858 | |
859 | The property of lower case before uppercase letters in EBCDIC is |
860 | even carried to the Latin 1 EBCDIC pages such as 0037 and 1047. |
b3b6085d |
861 | An example would be that E<Euml> C<E WITH DIAERESIS> (203) comes |
862 | before E<euml> C<e WITH DIAERESIS> (235) on an ASCII machine, but |
51b5cecb |
863 | the latter (83) comes before the former (115) on an EBCDIC machine. |
b3b6085d |
864 | (Astute readers will note that the upper case version of E<szlig> |
51b5cecb |
865 | C<SMALL LETTER SHARP S> is simply "SS" and that the upper case version of |
b3b6085d |
866 | E<yuml> C<y WITH DIAERESIS> is not in the 0..255 range but it is |
51b5cecb |
867 | at U+x0178 in Unicode, or C<"\x{178}"> in a Unicode enabled Perl). |
d396a558 |
868 | |
869 | The sort order will cause differences between results obtained on |
870 | ASCII machines versus EBCDIC machines. What follows are some suggestions |
871 | on how to deal with these differences. |
872 | |
51b5cecb |
873 | =head2 Ignore ASCII vs. EBCDIC sort differences. |
d396a558 |
874 | |
875 | This is the least computationally expensive strategy. It may require |
876 | some user education. |
877 | |
51b5cecb |
878 | =head2 MONO CASE then sort data. |
d396a558 |
879 | |
51b5cecb |
880 | In order to minimize the expense of mono casing mixed test try to |
d396a558 |
881 | C<tr///> towards the character set case most employed within the data. |
882 | If the data are primarily UPPERCASE non Latin 1 then apply tr/[a-z]/[A-Z]/ |
883 | then sort(). If the data are primarily lowercase non Latin 1 then |
884 | apply tr/[A-Z]/[a-z]/ before sorting. If the data are primarily UPPERCASE |
51b5cecb |
885 | and include Latin-1 characters then apply: |
886 | |
887 | tr/[a-z]/[A-Z]/; |
888 | tr/[àáâãäåæçèéêëìíîïðñòóôõöøùúûüýþ]/[ÀÁÂÃÄÅÆÇÈÉÊËÌÍÎÏÐÑÒÓÔÕÖØÙÚÛÜÝÞ]/; |
889 | s/ß/SS/g; |
d396a558 |
890 | |
51b5cecb |
891 | then sort(). Do note however that such Latin-1 manipulation does not |
b3b6085d |
892 | address the E<yuml> C<y WITH DIAERESIS> character that will remain at |
893 | code point 255 on ASCII machines, but 223 on most EBCDIC machines |
51b5cecb |
894 | where it will sort to a place less than the EBCDIC numerals. With a |
895 | Unicode enabled Perl you might try: |
d396a558 |
896 | |
51b5cecb |
897 | tr/^?/\x{178}/; |
898 | |
899 | The strategy of mono casing data before sorting does not preserve the case |
900 | of the data and may not be acceptable for that reason. |
901 | |
902 | =head2 Convert, sort data, then re convert. |
d396a558 |
903 | |
904 | This is the most expensive proposition that does not employ a network |
905 | connection. |
906 | |
907 | =head2 Perform sorting on one type of machine only. |
908 | |
909 | This strategy can employ a network connection. As such |
910 | it would be computationally expensive. |
911 | |
1e054b24 |
912 | =head1 TRANFORMATION FORMATS |
913 | |
914 | There are a variety of ways of transforming data with an intra character set |
915 | mapping that serve a variety of purposes. Sorting was discussed in the |
916 | previous section and a few of the other more popular mapping techniques are |
917 | discussed next. |
918 | |
919 | =head2 URL decoding and encoding |
d396a558 |
920 | |
51b5cecb |
921 | Note that some URLs have hexadecimal ASCII code points in them in an |
1e054b24 |
922 | attempt to overcome character or protocol limitation issues. For example |
923 | the tilde character is not on every keyboard hence a URL of the form: |
d396a558 |
924 | |
925 | http://www.pvhp.com/~pvhp/ |
926 | |
927 | may also be expressed as either of: |
928 | |
929 | http://www.pvhp.com/%7Epvhp/ |
930 | |
931 | http://www.pvhp.com/%7epvhp/ |
932 | |
51b5cecb |
933 | where 7E is the hexadecimal ASCII code point for '~'. Here is an example |
d396a558 |
934 | of decoding such a URL under CCSID 1047: |
935 | |
936 | $url = 'http://www.pvhp.com/%7Epvhp/'; |
937 | # this array assumes code page 1047 |
938 | my @a2e_1047 = ( |
939 | 0, 1, 2, 3, 55, 45, 46, 47, 22, 5, 21, 11, 12, 13, 14, 15, |
940 | 16, 17, 18, 19, 60, 61, 50, 38, 24, 25, 63, 39, 28, 29, 30, 31, |
941 | 64, 90,127,123, 91,108, 80,125, 77, 93, 92, 78,107, 96, 75, 97, |
942 | 240,241,242,243,244,245,246,247,248,249,122, 94, 76,126,110,111, |
943 | 124,193,194,195,196,197,198,199,200,201,209,210,211,212,213,214, |
944 | 215,216,217,226,227,228,229,230,231,232,233,173,224,189, 95,109, |
945 | 121,129,130,131,132,133,134,135,136,137,145,146,147,148,149,150, |
946 | 151,152,153,162,163,164,165,166,167,168,169,192, 79,208,161, 7, |
947 | 32, 33, 34, 35, 36, 37, 6, 23, 40, 41, 42, 43, 44, 9, 10, 27, |
948 | 48, 49, 26, 51, 52, 53, 54, 8, 56, 57, 58, 59, 4, 20, 62,255, |
949 | 65,170, 74,177,159,178,106,181,187,180,154,138,176,202,175,188, |
950 | 144,143,234,250,190,160,182,179,157,218,155,139,183,184,185,171, |
951 | 100,101, 98,102, 99,103,158,104,116,113,114,115,120,117,118,119, |
952 | 172,105,237,238,235,239,236,191,128,253,254,251,252,186,174, 89, |
953 | 68, 69, 66, 70, 67, 71,156, 72, 84, 81, 82, 83, 88, 85, 86, 87, |
954 | 140, 73,205,206,203,207,204,225,112,221,222,219,220,141,142,223 |
955 | ); |
956 | $url =~ s/%([0-9a-fA-F]{2})/pack("c",$a2e_1047[hex($1)])/ge; |
957 | |
1e054b24 |
958 | Conversely, here is a partial solution for the task of encoding such |
959 | a URL under the 1047 code page: |
960 | |
961 | $url = 'http://www.pvhp.com/~pvhp/'; |
962 | # this array assumes code page 1047 |
963 | my @e2a_1047 = ( |
964 | 0, 1, 2, 3,156, 9,134,127,151,141,142, 11, 12, 13, 14, 15, |
965 | 16, 17, 18, 19,157, 10, 8,135, 24, 25,146,143, 28, 29, 30, 31, |
966 | 128,129,130,131,132,133, 23, 27,136,137,138,139,140, 5, 6, 7, |
967 | 144,145, 22,147,148,149,150, 4,152,153,154,155, 20, 21,158, 26, |
968 | 32,160,226,228,224,225,227,229,231,241,162, 46, 60, 40, 43,124, |
969 | 38,233,234,235,232,237,238,239,236,223, 33, 36, 42, 41, 59, 94, |
970 | 45, 47,194,196,192,193,195,197,199,209,166, 44, 37, 95, 62, 63, |
971 | 248,201,202,203,200,205,206,207,204, 96, 58, 35, 64, 39, 61, 34, |
972 | 216, 97, 98, 99,100,101,102,103,104,105,171,187,240,253,254,177, |
973 | 176,106,107,108,109,110,111,112,113,114,170,186,230,184,198,164, |
974 | 181,126,115,116,117,118,119,120,121,122,161,191,208, 91,222,174, |
975 | 172,163,165,183,169,167,182,188,189,190,221,168,175, 93,180,215, |
976 | 123, 65, 66, 67, 68, 69, 70, 71, 72, 73,173,244,246,242,243,245, |
977 | 125, 74, 75, 76, 77, 78, 79, 80, 81, 82,185,251,252,249,250,255, |
978 | 92,247, 83, 84, 85, 86, 87, 88, 89, 90,178,212,214,210,211,213, |
979 | 48, 49, 50, 51, 52, 53, 54, 55, 56, 57,179,219,220,217,218,159 |
980 | ); |
981 | # The following regular expression does not address the |
982 | # mappings for: ('.' => '%2E', '/' => '%2F', ':' => '%3A') |
983 | $url =~ s/([\t "#%&\(\),;<=>\?\@\[\\\]^`{|}~])/sprintf("%%%02X",$e2a_1047[ord($1)])/ge; |
984 | |
985 | where a more complete solution would split the URL into components |
986 | and apply a full s/// substitution only to the appropriate parts. |
987 | |
988 | In the remaining examples a @e2a or @a2e array may be employed |
989 | but the assignment will not be shown explicitly. For code page 1047 |
990 | you could use the @a2e_1047 or @e2a_1047 arrays just shown. |
991 | |
992 | =head2 uu encoding and decoding |
993 | |
994 | The C<u> template to pack() or unpack() will render EBCDIC data in EBCDIC |
995 | characters equivalent to their ASCII counterparts. For example, the |
996 | following will print "Yes indeed\n" on either an ASCII or EBCDIC computer: |
997 | |
998 | $all_byte_chrs = ''; |
999 | for (0..255) { $all_byte_chrs .= chr($_); } |
1000 | $uuencode_byte_chrs = pack('u', $all_byte_chrs); |
1001 | ($uu = <<' ENDOFHEREDOC') =~ s/^\s*//gm; |
1002 | M``$"`P0%!@<("0H+#`T.#Q`1$A,4%187&!D:&QP='A\@(2(C)"4F)R@I*BLL |
1003 | M+2XO,#$R,S0U-C<X.3H[/#T^/T!!0D-$149'2$E*2TQ-3D]045)35%565UA9 |
1004 | M6EM<75Y?8&%B8V1E9F=H:6IK;&UN;W!Q<G-T=79W>'EZ>WQ]?G^`@8*#A(6& |
1005 | MAXB)BHN,C8Z/D)&2DY25EI>8F9J;G)V>GZ"AHJ.DI::GJ*FJJZRMKJ^PL;*S |
1006 | MM+6VM[BYNKN\O;Z_P,'"P\3%QL?(R<K+S,W.S]#1TM/4U=;7V-G:V]S=WM_@ |
1007 | ?X>+CY.7FY^CIZNOL[>[O\/'R\_3U]O?X^?K[_/W^_P`` |
1008 | ENDOFHEREDOC |
1009 | if ($uuencode_byte_chrs eq $uu) { |
1010 | print "Yes "; |
1011 | } |
1012 | $uudecode_byte_chrs = unpack('u', $uuencode_byte_chrs); |
1013 | if ($uudecode_byte_chrs eq $all_byte_chrs) { |
1014 | print "indeed\n"; |
1015 | } |
1016 | |
1017 | Here is a very spartan uudecoder that will work on EBCDIC provided |
1018 | that the @e2a array is filled in appropriately: |
1019 | |
1020 | #!/usr/local/bin/perl |
1021 | @e2a = ( # this must be filled in |
1022 | ); |
1023 | $_ = <> until ($mode,$file) = /^begin\s*(\d*)\s*(\S*)/; |
1024 | open(OUT, "> $file") if $file ne ""; |
1025 | while(<>) { |
1026 | last if /^end/; |
1027 | next if /[a-z]/; |
1028 | next unless int(((($e2a[ord()] - 32 ) & 077) + 2) / 3) == |
1029 | int(length() / 4); |
1030 | print OUT unpack("u", $_); |
1031 | } |
1032 | close(OUT); |
1033 | chmod oct($mode), $file; |
1034 | |
1035 | |
1036 | =head2 Quoted-Printable encoding and decoding |
1037 | |
1038 | On ASCII encoded machines it is possible to strip characters outside of |
1039 | the printable set using: |
1040 | |
1041 | # This QP encoder works on ASCII only |
1042 | $qp_string =~ s/([=\x00-\x1F\x80-\xFF])/sprintf("=%02X",ord($1))/ge; |
1043 | |
1044 | Whereas a QP encoder that works on both ASCII and EBCDIC machines |
1045 | would look somewhat like the following (where the EBCDIC branch @e2a |
1046 | array is omitted for brevity): |
1047 | |
1048 | if (ord('A') == 65) { # ASCII |
1049 | $delete = "\x7F"; # ASCII |
1050 | @e2a = (0 .. 255) # ASCII to ASCII identity map |
1051 | } |
1052 | else { # EBCDIC |
1053 | $delete = "\x07"; # EBCDIC |
1054 | @e2a = # EBCDIC to ASCII map (as shown above) |
1055 | } |
1056 | $qp_string =~ |
1057 | s/([^ !"\#\$%&'()*+,\-.\/0-9:;<>?\@A-Z[\\\]^_`a-z{|}~$delete])/sprintf("=%02X",$e2a[ord($1)])/ge; |
1058 | |
1059 | (although in production code the substitutions might be done |
1060 | in the EBCDIC branch with the @e2a array and separately in the |
1061 | ASCII branch without the expense of the identity map). |
1062 | |
1063 | Such QP strings can be decoded with: |
1064 | |
1065 | # This QP decoder is limited to ASCII only |
1066 | $string =~ s/=([0-9A-Fa-f][0-9A-Fa-f])/chr hex $1/ge; |
1067 | $string =~ s/=[\n\r]+$//; |
1068 | |
1069 | Whereas a QP decoder that works on both ASCII and EBCDIC machines |
1070 | would look somewhat like the following (where the @a2e array is |
1071 | omitted for brevity): |
1072 | |
1073 | $string =~ s/=([0-9A-Fa-f][0-9A-Fa-f])/chr $a2e[hex $1]/ge; |
1074 | $string =~ s/=[\n\r]+$//; |
1075 | |
1076 | =head2 Caesarian cyphers |
1077 | |
1078 | The practice of shifting an alphabet one or more characters for encipherment |
1079 | dates back thousands of years and was explicitly detailed by Gaius Julius |
1080 | Caesar in his B<Gallic Wars> text. A single alphabet shift is sometimes |
1081 | referred to as a rotation and the shift amount is given as a number $n after |
1082 | the string 'rot' or "rot$n". Rot0 and rot26 would designate identity maps |
1083 | on the 26 letter English version of the Latin alphabet. Rot13 has the |
1084 | interesting property that alternate subsequent invocations are identity maps |
1085 | (thus rot13 is its own non-trivial inverse in the group of 26 alphabet |
1086 | rotations). Hence the following is a rot13 encoder and decoder that will |
1087 | work on ASCII and EBCDIC machines: |
1088 | |
1089 | #!/usr/local/bin/perl |
1090 | |
1091 | while(<>){ |
1092 | tr/n-za-mN-ZA-M/a-zA-Z/; |
1093 | print; |
1094 | } |
1095 | |
1096 | In one-liner form: |
1097 | |
1098 | perl -ne 'tr/n-za-mN-ZA-M/a-zA-Z/;print' |
1099 | |
1100 | |
1101 | =head1 Hashing order and checksums |
1102 | |
1103 | XXX |
1104 | |
d396a558 |
1105 | =head1 I18N AND L10N |
1106 | |
1107 | Internationalization(I18N) and localization(L10N) are supported at least |
1108 | in principle even on EBCDIC machines. The details are system dependent |
1109 | and discussed under the L<perlebcdic/OS ISSUES> section below. |
1110 | |
1111 | =head1 MULTI OCTET CHARACTER SETS |
1112 | |
51b5cecb |
1113 | Multi byte EBCDIC code pages; Unicode, UTF-8, UTF-EBCDIC, XXX. |
d396a558 |
1114 | |
1115 | =head1 OS ISSUES |
1116 | |
1117 | There may be a few system dependent issues |
1118 | of concern to EBCDIC Perl programmers. |
1119 | |
1120 | =head2 OS/400 |
1121 | |
51b5cecb |
1122 | The PASE environment. |
1123 | |
d396a558 |
1124 | =over 8 |
1125 | |
1126 | =item IFS access |
1127 | |
1128 | XXX. |
1129 | |
1130 | =back |
1131 | |
1132 | =head2 OS/390 |
1133 | |
51b5cecb |
1134 | Perl runs under Unix Systems Services or USS. |
1135 | |
d396a558 |
1136 | =over 8 |
1137 | |
51b5cecb |
1138 | =item chcp |
1139 | |
1e054b24 |
1140 | B<chcp> is supported as a shell utility for displaying and changing |
1141 | one's code page. See also L<chcp>. |
51b5cecb |
1142 | |
d396a558 |
1143 | =item dataset access |
1144 | |
1145 | For sequential data set access try: |
1146 | |
1147 | my @ds_records = `cat //DSNAME`; |
1148 | |
1149 | or: |
1150 | |
1151 | my @ds_records = `cat //'HLQ.DSNAME'`; |
1152 | |
1153 | See also the OS390::Stdio module on CPAN. |
1154 | |
1e054b24 |
1155 | =item OS/390 iconv |
51b5cecb |
1156 | |
1e054b24 |
1157 | B<iconv> is supported as both a shell utility and a C RTL routine. |
1158 | See also the iconv(1) and iconv(3) manual pages. |
51b5cecb |
1159 | |
d396a558 |
1160 | =item locales |
1161 | |
1162 | On OS/390 see L<locale> for information on locales. The L10N files |
1163 | are in F</usr/nls/locale>. $Config{d_setlocale} is 'define' on OS/390. |
1164 | |
1165 | =back |
1166 | |
1167 | =head2 VM/ESA? |
1168 | |
1169 | XXX. |
1170 | |
1171 | =head2 POSIX-BC? |
1172 | |
1173 | XXX. |
1174 | |
51b5cecb |
1175 | =head1 BUGS |
1176 | |
1177 | This pod document contains literal Latin 1 characters and may encounter |
b1866b2d |
1178 | translation difficulties. In particular one popular nroff implementation |
51b5cecb |
1179 | was known to strip accented characters to their unaccented counterparts |
1180 | while attempting to view this document through the B<pod2man> program |
1181 | (for example, you may see a plain C<y> rather than one with a diaeresis |
b3b6085d |
1182 | as in E<yuml>). Another nroff truncated the resultant man page at |
1183 | the first occurence of 8 bit characters. |
51b5cecb |
1184 | |
1185 | Not all shells will allow multiple C<-e> string arguments to perl to |
1186 | be concatenated together properly as recipes 2, 3, and 4 might seem |
1187 | to imply. |
1188 | |
1189 | Perl does not yet work with any Unicode features on EBCDIC platforms. |
1190 | |
b3b6085d |
1191 | =head1 SEE ALSO |
1192 | |
1193 | L<perllocale>, L<perlfunc>. |
1194 | |
d396a558 |
1195 | =head1 REFERENCES |
1196 | |
1197 | http://anubis.dkuug.dk/i18n/charmaps |
1198 | |
d396a558 |
1199 | http://www.unicode.org/ |
1200 | |
1201 | http://www.unicode.org/unicode/reports/tr16/ |
1202 | |
51b5cecb |
1203 | http://www.wps.com/texts/codes/ |
1204 | B<ASCII: American Standard Code for Information Infiltration> Tom Jennings, |
1205 | September 1999. |
1206 | |
d396a558 |
1207 | B<The Unicode Standard Version 2.0> The Unicode Consortium, |
1208 | ISBN 0-201-48345-9, Addison Wesley Developers Press, July 1996. |
1209 | |
51b5cecb |
1210 | B<The Unicode Standard Version 3.0> The Unicode Consortium, Lisa Moore ed., |
1211 | ISBN 0-201-61633-5, Addison Wesley Developers Press, February 2000. |
1212 | |
d396a558 |
1213 | B<CDRA: IBM - Character Data Representation Architecture - |
1214 | Reference and Registry>, IBM SC09-2190-00, December 1996. |
1215 | |
1216 | "Demystifying Character Sets", Andrea Vine, Multilingual Computing |
1217 | & Technology, B<#26 Vol. 10 Issue 4>, August/September 1999; |
1218 | ISSN 1523-0309; Multilingual Computing Inc. Sandpoint ID, USA. |
1219 | |
1e054b24 |
1220 | B<Codes, Ciphers, and Other Cryptic and Clandestine Communication> |
1221 | Fred B. Wrixon, ISBN 1-57912-040-7, Black Dog & Leventhal Publishers, |
1222 | 1998. |
1223 | |
d396a558 |
1224 | =head1 AUTHOR |
1225 | |
b3b6085d |
1226 | Peter Prymmer pvhp@best.com wrote this in 1999 and 2000 |
d396a558 |
1227 | with CCSID 0819 and 0037 help from Chris Leach and |
b3b6085d |
1228 | AndrE<eacute> Pirard A.Pirard@ulg.ac.be as well as POSIX-BC |
1229 | help from Thomas Dorner Thomas.Dorner@start.de. |
1e054b24 |
1230 | Thanks also to Vickie Cooper, Philip Newton, William Raffloer, and |
1231 | Joe Smith. Trademarks, registered trademarks, service marks and |
1232 | registered service marks used in this document are the property of |
1233 | their respective owners. |
d396a558 |
1234 | |
1235 | |