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perlebcdic - Considerations for running Perl on EBCDIC platforms
An exploration of some of the issues facing Perl programmers
on EBCDIC based computers. We do not cover localization,
internationalization, or multi byte character set issues other
than some discussion of UTF-8 and UTF-EBCDIC.
Portions that are still incomplete are marked with XXX.
The American Standard Code for Information Interchange is a set of
integers running from 0 to 127 (decimal) that imply character
interpretation by the display and other system(s) of computers.
The range 0..127 can be covered by setting the bits in a 7-bit binary
digit, hence the set is sometimes referred to as a "7-bit ASCII".
ASCII was described by the American National Standards Institute
document ANSI X3.4-1986. It was also described by ISO 646:1991
(with localization for currency symbols). The full ASCII set is
given in the table below as the first 128 elements. Languages that
can be written adequately with the characters in ASCII include
English, Hawaiian, Indonesian, Swahili and some Native American
languages.
There are many character sets that extend the range of integers
from 0..2**7-1 up to 2**8-1, or 8 bit bytes (octets if you prefer).
One common one is the ISO 8859-1 character set.
The ISO 8859-$n are a collection of character code sets from the
International Organization for Standardization (ISO) each of which
adds characters to the ASCII set that are typically found in European
languages many of which are based on the Roman, or Latin, alphabet.
A particular 8-bit extension to ASCII that includes grave and acute
accented Latin characters. Languages that can employ ISO 8859-1
include all the languages covered by ASCII as well as Afrikaans,
Albanian, Basque, Catalan, Danish, Faroese, Finnish, Norwegian,
Portuguese, Spanish, and Swedish. Dutch is covered albeit without
the ij ligature. French is covered too but without the oe ligature.
German can use ISO 8859-1 but must do so without German-style
quotation marks. This set is based on Western European extensions
to ASCII and is commonly encountered in world wide web work.
In IBM character code set identification terminology ISO 8859-1 is
also known as CCSID 819 (or sometimes 0819 or even 00819).
The Extended Binary Coded Decimal Interchange Code refers to a
large collection of slightly different single and multi byte
coded character sets that are different from ASCII or ISO 8859-1
and typically run on host computers. The EBCDIC encodings derive
from 8 bit byte extensions of Hollerith punched card encodings.
The layout on the cards was such that high bits were set for the
upper and lower case alphabet characters [a-z] and [A-Z], but there
were gaps within each latin alphabet range.
Some IBM EBCDIC character sets may be known by character code set
identification numbers (CCSID numbers) or code page numbers. Leading
zero digits in CCSID numbers within this document are insignificant.
E.g. CCSID 0037 may be referred to as 37 in places.
Among IBM EBCDIC character code sets there are 13 characters that
are often mapped to different integer values. Those characters
are known as the 13 "variant" characters and are:
\ [ ] { } ^ ~ !
Character code set ID 0037 is a mapping of the ASCII plus Latin-1
characters (i.e. ISO 8859-1) to an EBCDIC set. 0037 is used
in North American English locales on the OS/400 operating system
that runs on AS/400 computers. CCSID 37 differs from ISO 8859-1
in 237 places, in other words they agree on only 19 code point values.
Character code set ID 1047 is also a mapping of the ASCII plus
Latin-1 characters (i.e. ISO 8859-1) to an EBCDIC set. 1047 is
used under Unix System Services for OS/390 or z/OS, and OpenEdition
for VM/ESA. CCSID 1047 differs from CCSID 0037 in eight places.
The EBCDIC code page in use on Siemens' BS2000 system is distinct from
1047 and 0037. It is identified below as the POSIX-BC set.
In Unicode terminology a code point is the number assigned to a
character: for example, in EBCDIC the character "A" is usually assigned
the number 193. In Unicode the character "A" is assigned the number 65.
This causes a problem with the semantics of the pack/unpack "U", which
are supposed to pack Unicode code points to characters and back to numbers.
The problem is: which code points to use for code points less than 256?
(for 256 and over there's no problem: Unicode code points are used)
In EBCDIC, for the low 256 the EBCDIC code points are used. This
means that the equivalences
pack("U", ord($character)) eq $character
unpack("U", $character) == ord $character
will hold. (If Unicode code points were applied consistently over
all the possible code points, pack("U",ord("A")) would in EBCDIC
equal A with acute or chr(101), and unpack("U", "A") would equal
65, or non-breaking space, not 193, or ord "A".)
-
Many of the remaining seem to be related to case-insensitive matching:
for example, /[\x{131}]/ (LATIN SMALL LETTER DOTLESS I) does
not match "I" case-insensitively, as it should under Unicode.
(The match succeeds in ASCII-derived platforms.)
-
The extensions Unicode::Collate and Unicode::Normalized are not
supported under EBCDIC, likewise for the encoding pragma.
UTF is a Unicode Transformation Format. UTF-8 is a Unicode conforming
representation of the Unicode standard that looks very much like ASCII.
UTF-EBCDIC is an attempt to represent Unicode characters in an EBCDIC
transparent manner.
Starting from Perl 5.8 you can use the standard new module Encode
to translate from EBCDIC to Latin-1 code points
use Encode 'from_to';
my %ebcdic = ( 176 => 'cp37', 95 => 'cp1047', 106 => 'posix-bc' );
from_to($a, $ebcdic{ord '^'}, 'latin1');
and from Latin-1 code points to EBCDIC code points
use Encode 'from_to';
my %ebcdic = ( 176 => 'cp37', 95 => 'cp1047', 106 => 'posix-bc' );
from_to($a, 'latin1', $ebcdic{ord '^'});
For doing I/O it is suggested that you use the autotranslating features
of PerlIO, see the perluniintro manpage.
Since version 5.8 Perl uses the new PerlIO I/O library. This enables
you to use different encodings per IO channel. For example you may use
use Encode;
open($f, ">:encoding(ascii)", "test.ascii");
print $f "Hello World!\n";
open($f, ">:encoding(cp37)", "test.ebcdic");
print $f "Hello World!\n";
open($f, ">:encoding(latin1)", "test.latin1");
print $f "Hello World!\n";
open($f, ">:encoding(utf8)", "test.utf8");
print $f "Hello World!\n";
to get two files containing "Hello World!\n" in ASCII, CP 37 EBCDIC,
ISO 8859-1 (Latin-1) (in this example identical to ASCII) respective
UTF-EBCDIC (in this example identical to normal EBCDIC). See the
documentation of Encode::PerlIO for details.
As the PerlIO layer uses raw IO (bytes) internally, all this totally
ignores things like the type of your filesystem (ASCII or EBCDIC).
The following tables list the ASCII and Latin 1 ordered sets including
the subsets: C0 controls (0..31), ASCII graphics (32..7e), delete (7f),
C1 controls (80..9f), and Latin-1 (a.k.a. ISO 8859-1) (a0..ff). In the
table non-printing control character names as well as the Latin 1
extensions to ASCII have been labelled with character names roughly
corresponding to The Unicode Standard, Version 3.0 albeit with
substitutions such as s/LATIN// and s/VULGAR// in all cases,
s/CAPITAL LETTER// in some cases, and s/SMALL LETTER ([A-Z])/\l$1/
in some other cases (the charnames pragma names unfortunately do
not list explicit names for the C0 or C1 control characters). The
"names" of the C1 control set (128..159 in ISO 8859-1) listed here are
somewhat arbitrary. The differences between the 0037 and 1047 sets are
flagged with ***. The differences between the 1047 and POSIX-BC sets
are flagged with ###. All ord() numbers listed are decimal. If you
would rather see this table listing octal values then run the table
(that is, the pod version of this document since this recipe may not
work with a pod2_other_format translation) through:
- recipe 0
perl -ne 'if(/(.{33})(\d+)\s+(\d+)\s+(\d+)\s+(\d+)/)' \
-e '{printf("%s%-9o%-9o%-9o%o\n",$1,$2,$3,$4,$5)}' perlebcdic.pod
If you want to retain the UTF-x code points then in script form you
might want to write:
- recipe 1
open(FH,"<perlebcdic.pod") or die "Could not open perlebcdic.pod: $!";
while (<FH>) {
if (/(.{33})(\d+)\s+(\d+)\s+(\d+)\s+(\d+)\s+(\d+)\.?(\d*)\s+(\d+)\.?(\d*)/) {
if ($7 ne '' && $9 ne '') {
printf("%s%-9o%-9o%-9o%-9o%-3o.%-5o%-3o.%o\n",$1,$2,$3,$4,$5,$6,$7,$8,$9);
}
elsif ($7 ne '') {
printf("%s%-9o%-9o%-9o%-9o%-3o.%-5o%o\n",$1,$2,$3,$4,$5,$6,$7,$8);
}
else {
printf("%s%-9o%-9o%-9o%-9o%-9o%o\n",$1,$2,$3,$4,$5,$6,$8);
}
}
}
If you would rather see this table listing hexadecimal values then
run the table through:
- recipe 2
perl -ne 'if(/(.{33})(\d+)\s+(\d+)\s+(\d+)\s+(\d+)/)' \
-e '{printf("%s%-9X%-9X%-9X%X\n",$1,$2,$3,$4,$5)}' perlebcdic.pod
Or, in order to retain the UTF-x code points in hexadecimal:
- recipe 3
open(FH,"<perlebcdic.pod") or die "Could not open perlebcdic.pod: $!";
while (<FH>) {
if (/(.{33})(\d+)\s+(\d+)\s+(\d+)\s+(\d+)\s+(\d+)\.?(\d*)\s+(\d+)\.?(\d*)/) {
if ($7 ne '' && $9 ne '') {
printf("%s%-9X%-9X%-9X%-9X%-2X.%-6X%-2X.%X\n",$1,$2,$3,$4,$5,$6,$7,$8,$9);
}
elsif ($7 ne '') {
printf("%s%-9X%-9X%-9X%-9X%-2X.%-6X%X\n",$1,$2,$3,$4,$5,$6,$7,$8);
}
else {
printf("%s%-9X%-9X%-9X%-9X%-9X%X\n",$1,$2,$3,$4,$5,$6,$8);
}
}
}
incomp- incomp-
8859-1 lete lete
chr 0819 0037 1047 POSIX-BC UTF-8 UTF-EBCDIC
------------------------------------------------------------------------------------
<NULL> 0 0 0 0 0 0
<START OF HEADING> 1 1 1 1 1 1
<START OF TEXT> 2 2 2 2 2 2
<END OF TEXT> 3 3 3 3 3 3
<END OF TRANSMISSION> 4 55 55 55 4 55
<ENQUIRY> 5 45 45 45 5 45
<ACKNOWLEDGE> 6 46 46 46 6 46
<BELL> 7 47 47 47 7 47
<BACKSPACE> 8 22 22 22 8 22
<HORIZONTAL TABULATION> 9 5 5 5 9 5
<LINE FEED> 10 37 21 21 10 21 ***
<VERTICAL TABULATION> 11 11 11 11 11 11
<FORM FEED> 12 12 12 12 12 12
<CARRIAGE RETURN> 13 13 13 13 13 13
<SHIFT OUT> 14 14 14 14 14 14
<SHIFT IN> 15 15 15 15 15 15
<DATA LINK ESCAPE> 16 16 16 16 16 16
<DEVICE CONTROL ONE> 17 17 17 17 17 17
<DEVICE CONTROL TWO> 18 18 18 18 18 18
<DEVICE CONTROL THREE> 19 19 19 19 19 19
<DEVICE CONTROL FOUR> 20 60 60 60 20 60
<NEGATIVE ACKNOWLEDGE> 21 61 61 61 21 61
<SYNCHRONOUS IDLE> 22 50 50 50 22 50
<END OF TRANSMISSION BLOCK> 23 38 38 38 23 38
<CANCEL> 24 24 24 24 24 24
<END OF MEDIUM> 25 25 25 25 25 25
<SUBSTITUTE> 26 63 63 63 26 63
<ESCAPE> 27 39 39 39 27 39
<FILE SEPARATOR> 28 28 28 28 28 28
<GROUP SEPARATOR> 29 29 29 29 29 29
<RECORD SEPARATOR> 30 30 30 30 30 30
<UNIT SEPARATOR> 31 31 31 31 31 31
<SPACE> 32 64 64 64 32 64
! 33 90 90 90 33 90
" 34 127 127 127 34 127
# 35 123 123 123 35 123
$ 36 91 91 91 36 91
% 37 108 108 108 37 108
& 38 80 80 80 38 80
' 39 125 125 125 39 125
( 40 77 77 77 40 77
) 41 93 93 93 41 93
* 42 92 92 92 42 92
+ 43 78 78 78 43 78
, 44 107 107 107 44 107
- 45 96 96 96 45 96
. 46 75 75 75 46 75
/ 47 97 97 97 47 97
0 48 240 240 240 48 240
1 49 241 241 241 49 241
2 50 242 242 242 50 242
3 51 243 243 243 51 243
4 52 244 244 244 52 244
5 53 245 245 245 53 245
6 54 246 246 246 54 246
7 55 247 247 247 55 247
8 56 248 248 248 56 248
9 57 249 249 249 57 249
: 58 122 122 122 58 122
; 59 94 94 94 59 94
< 60 76 76 76 60 76
= 61 126 126 126 61 126
> 62 110 110 110 62 110
? 63 111 111 111 63 111
@ 64 124 124 124 64 124
A 65 193 193 193 65 193
B 66 194 194 194 66 194
C 67 195 195 195 67 195
D 68 196 196 196 68 196
E 69 197 197 197 69 197
F 70 198 198 198 70 198
G 71 199 199 199 71 199
H 72 200 200 200 72 200
I 73 201 201 201 73 201
J 74 209 209 209 74 209
K 75 210 210 210 75 210
L 76 211 211 211 76 211
M 77 212 212 212 77 212
N 78 213 213 213 78 213
O 79 214 214 214 79 214
P 80 215 215 215 80 215
Q 81 216 216 216 81 216
R 82 217 217 217 82 217
S 83 226 226 226 83 226
T 84 227 227 227 84 227
U 85 228 228 228 85 228
V 86 229 229 229 86 229
W 87 230 230 230 87 230
X 88 231 231 231 88 231
Y 89 232 232 232 89 232
Z 90 233 233 233 90 233
[ 91 186 173 187 91 173 *** ###
\ 92 224 224 188 92 224 ###
] 93 187 189 189 93 189 ***
^ 94 176 95 106 94 95 *** ###
_ 95 109 109 109 95 109
` 96 121 121 74 96 121 ###
a 97 129 129 129 97 129
b 98 130 130 130 98 130
c 99 131 131 131 99 131
d 100 132 132 132 100 132
e 101 133 133 133 101 133
f 102 134 134 134 102 134
g 103 135 135 135 103 135
h 104 136 136 136 104 136
i 105 137 137 137 105 137
j 106 145 145 145 106 145
k 107 146 146 146 107 146
l 108 147 147 147 108 147
m 109 148 148 148 109 148
n 110 149 149 149 110 149
o 111 150 150 150 111 150
p 112 151 151 151 112 151
q 113 152 152 152 113 152
r 114 153 153 153 114 153
s 115 162 162 162 115 162
t 116 163 163 163 116 163
u 117 164 164 164 117 164
v 118 165 165 165 118 165
w 119 166 166 166 119 166
x 120 167 167 167 120 167
y 121 168 168 168 121 168
z 122 169 169 169 122 169
{ 123 192 192 251 123 192 ###
| 124 79 79 79 124 79
} 125 208 208 253 125 208 ###
~ 126 161 161 255 126 161 ###
<DELETE> 127 7 7 7 127 7
<C1 0> 128 32 32 32 194.128 32
<C1 1> 129 33 33 33 194.129 33
<C1 2> 130 34 34 34 194.130 34
<C1 3> 131 35 35 35 194.131 35
<C1 4> 132 36 36 36 194.132 36
<C1 5> 133 21 37 37 194.133 37 ***
<C1 6> 134 6 6 6 194.134 6
<C1 7> 135 23 23 23 194.135 23
<C1 8> 136 40 40 40 194.136 40
<C1 9> 137 41 41 41 194.137 41
<C1 10> 138 42 42 42 194.138 42
<C1 11> 139 43 43 43 194.139 43
<C1 12> 140 44 44 44 194.140 44
<C1 13> 141 9 9 9 194.141 9
<C1 14> 142 10 10 10 194.142 10
<C1 15> 143 27 27 27 194.143 27
<C1 16> 144 48 48 48 194.144 48
<C1 17> 145 49 49 49 194.145 49
<C1 18> 146 26 26 26 194.146 26
<C1 19> 147 51 51 51 194.147 51
<C1 20> 148 52 52 52 194.148 52
<C1 21> 149 53 53 53 194.149 53
<C1 22> 150 54 54 54 194.150 54
<C1 23> 151 8 8 8 194.151 8
<C1 24> 152 56 56 56 194.152 56
<C1 25> 153 57 57 57 194.153 57
<C1 26> 154 58 58 58 194.154 58
<C1 27> 155 59 59 59 194.155 59
<C1 28> 156 4 4 4 194.156 4
<C1 29> 157 20 20 20 194.157 20
<C1 30> 158 62 62 62 194.158 62
<C1 31> 159 255 255 95 194.159 255 ###
<NON-BREAKING SPACE> 160 65 65 65 194.160 128.65
<INVERTED EXCLAMATION MARK> 161 170 170 170 194.161 128.66
<CENT SIGN> 162 74 74 176 194.162 128.67 ###
<POUND SIGN> 163 177 177 177 194.163 128.68
<CURRENCY SIGN> 164 159 159 159 194.164 128.69
<YEN SIGN> 165 178 178 178 194.165 128.70
<BROKEN BAR> 166 106 106 208 194.166 128.71 ###
<SECTION SIGN> 167 181 181 181 194.167 128.72
<DIAERESIS> 168 189 187 121 194.168 128.73 *** ###
<COPYRIGHT SIGN> 169 180 180 180 194.169 128.74
<FEMININE ORDINAL INDICATOR> 170 154 154 154 194.170 128.81
<LEFT POINTING GUILLEMET> 171 138 138 138 194.171 128.82
<NOT SIGN> 172 95 176 186 194.172 128.83 *** ###
<SOFT HYPHEN> 173 202 202 202 194.173 128.84
<REGISTERED TRADE MARK SIGN> 174 175 175 175 194.174 128.85
<MACRON> 175 188 188 161 194.175 128.86 ###
<DEGREE SIGN> 176 144 144 144 194.176 128.87
<PLUS-OR-MINUS SIGN> 177 143 143 143 194.177 128.88
<SUPERSCRIPT TWO> 178 234 234 234 194.178 128.89
<SUPERSCRIPT THREE> 179 250 250 250 194.179 128.98
<ACUTE ACCENT> 180 190 190 190 194.180 128.99
<MICRO SIGN> 181 160 160 160 194.181 128.100
<PARAGRAPH SIGN> 182 182 182 182 194.182 128.101
<MIDDLE DOT> 183 179 179 179 194.183 128.102
<CEDILLA> 184 157 157 157 194.184 128.103
<SUPERSCRIPT ONE> 185 218 218 218 194.185 128.104
<MASC. ORDINAL INDICATOR> 186 155 155 155 194.186 128.105
<RIGHT POINTING GUILLEMET> 187 139 139 139 194.187 128.106
<FRACTION ONE QUARTER> 188 183 183 183 194.188 128.112
<FRACTION ONE HALF> 189 184 184 184 194.189 128.113
<FRACTION THREE QUARTERS> 190 185 185 185 194.190 128.114
<INVERTED QUESTION MARK> 191 171 171 171 194.191 128.115
<A WITH GRAVE> 192 100 100 100 195.128 138.65
<A WITH ACU | 
