The regcmp command performs a function similar to regcmp and, in most cases, precludes the need for calling regcmp from C programs. Bypassing regcmp saves on both execution time and program size. The command regcmp compiles the regular expressions in filename and places the output in filename.i.
OPTIONS
-
If the - option is used, the output is placed in filename.c. The format of entries in filename is a name (C variable) followed by one or more blanks followed by one or more regular expressions
enclosed in double quotes. The output of regcmp is C source code. Compiled regular expressions are represented as extern char vectors. filename.i files may thus be #included in C programs, or filename.c files may be compiled and later loaded. In the C program that uses
the regcmp output, regex(abc,line) applies the regular expression named abc to line. Diagnostics are self-explanatory.
EXAMPLES
Example 1 Examples of the regcmp command.
name
"([A-Za-z][A-Za-z0-9_]*)$0"
telno
"\({0,1}([2-9][01][1-9])$0\){0,1} *"
"([2-9][0-9]{2})$1[ -]{0,1}"
"([0-9]{4})$2"
The three arguments to telno shown above must all be entered on one line.
In the C program that uses the regcmp output,
regex(telno, line, area, exch, rest)
applies the regular expression named telno to line.
ENVIRONMENT VARIABLES
A general description of the usage of the LC_* environmental variables can be found in environ(5).
LC_CTYPE
Determines how regcmp handles characters. When LC_CTYPE
is set to a valid value, regcmp can display and handle text and filenames containing valid characters for that locale.
LC_MESSAGES
Determines how diagnostic and informative messages are presented. This includes the language and style of the messages, and the correct
form of affirmative and negative responses. In the "C" locale, the messages are presented in the default form found in the program itself (in most cases, U.S. English).
ATTRIBUTES
See attributes(5) for descriptions of the following
attributes: