NAME

chrtbl − generate character classification and conversion tables

SYNOPSIS

chrtbl [file]

DESCRIPTION

The chrtbl command creates a character classification table and an upper/lower-case conversion table.  The tables are contained in a byte-sized array encoded such that a table lookup can be used to determine the character classification of a character or to convert a character [see ctype(3C)].  The size of the array is 257*2 bytes: 257 bytes are required for the 8-bit code set character classification table and 257 bytes for the upper- to lower-case and lower- to upper-case conversion table. 

chrtbl reads the user-defined character classification and conversion information from file and creates two output files in the current directory.  One output file, ctype.c (a C-language source file), contains the 257*2-byte array generated from processing the information from file. You should review the content of ctype.c to verify that the array is set up as you had planned.  (In addition, an application program could use ctype.c.)  The first 257 bytes of the array in ctype.c are used for character classification.  The characters used for initializing these bytes of the array represent character classifications that are defined in /usr/include/ctype.h; for example, _L means a character is lower case and _S│_B means the character is both a spacing character and a blank.  The last 257 bytes of the array are used for character conversion.  These bytes of the array are initialized so that characters for which you do not provide conversion information will be converted to themselves.  When you do provide conversion information, the first value of the pair is stored where the second one would be stored normally, and vice versa; for example, if you provide <0x41 0x61>, then 0x61 is stored where 0x41 would be stored normally, and 0x61 is stored where 0x41 would be stored normally. 

The second output file (a data file) contains the same information, but is structured for efficient use by the character classification and conversion routines [see ctype(3C)]. The name of this output file is the value of the character classification chrclass read in from file. This output file must be installed in the /lib/chrclass directory under this name by someone who is super-user or a member of group bin.  This file must be readable by user, group, and other; no other permissions should be set.  To use the character classification and conversion tables on this file, set the environmental variable CHRCLASS [see environ(5)] to the name of this file and export the variable; for example, if the name of this file (and character class) is xyz, you should issue the commands: CHRCLASS=xyz ; export CHRCLASS . 

If no input file is given, or if the argument − is encountered, chrtbl reads from the standard input file. 

The syntax of file allows the user to define the name of the data file created by chrtbl, the assignment of characters to character classifications and the relationship between upper- and lower-case letters.  The character classifications recognized by chrtbl are:

chrclass name of the data file to be created by chrtbl. 

isupper character codes to be classified as upper-case letters. 

islower character codes to be classified as lower-case letters. 

isdigit character codes to be classified as numeric. 

isspace character codes to be classified as a spacing ­(delimiter) character. 

ispunct character codes to be classified as a punctuation character. 

iscntrl character codes to be classified as a control character. 

isblank character code for the space character. 

isxdigit character codes to be classified as hexadecimal digits. 

ul relationship between upper- and lower-case characters. 

Any lines with the number sign (#) in the first column are treated as comments and are ignored.  Blank lines are also ignored. 

A character can be represented as a hexadecimal or octal constant (for example, the letter a can be represented as 0x61 in hexadecimal or 0141 in octal).  Hexadecimal and octal constants may be separated by one or more space and tab characters. 

The dash character (−) may be used to indicate a range of consecutive numbers.  Zero or more space characters may be used for separating the dash character from the numbers. 

The backslash character (\) is used for line continuation.  Only a carriage return is permitted after the backslash character. 

The relationship between upper- and lower-case letters (ul) is expressed as ordered pairs of octal or hexadecimal constants: <upper-case_character lower-case_character>.  These two constants may be separated by one or more space characters.  Zero or more space characters may be used for separating the angle brackets (< >) from the numbers. 

EXAMPLE

The following is an example of an input file used to create the ASCII code set definition table on a file named ascii:

FILES

/lib/chrclass/∗ data file containing character classification and conversion tables created by chrtbl

/usr/include/ctype.h
header file containing information used by character classification and conversion routines

SEE ALSO

ctype(3C), environ(5) in the INTER­ACTIVE SDS Guide and Programmer’s Reference Manual.

DIAGNOSTICS

The error messages produced by chrtbl are intended to be self-explanatory.  They indicate errors in the command line or syntactic errors encountered within the input file. 

\*U  —  Version 1.0