RE_COMP(3C) Standard C Library Functions RE_COMP(3C)
re_comp, re_exec - compile and execute regular expressions
#include <re_comp.h>
char *re_comp(const char *string);
int re_exec(const char *string);
The re_comp() function converts a regular expression string (RE) into
an internal form suitable for pattern matching. The re_exec()
function compares the string pointed to by the string argument with
the last regular expression passed to re_comp().
If re_comp() is called with a null pointer argument, the current
regular expression remains unchanged.
Strings passed to both re_comp() and re_exec() must be terminated by
a null byte, and may include NEWLINE characters.
The re_comp() and re_exec() functions support simple regular
expressions, which are defined on the regexp(7) manual page. The
regular expressions of the form \{m\}, \{m,\}, or \{m,n\} are not
supported.
The re_comp() function returns a null pointer when the string pointed
to by the string argument is successfully converted. Otherwise, a
pointer to one of the following error message strings is returned:
No previous regular expression
Regular expression too long
unmatched \(
missing ]
too many \(\) pairs
unmatched \)
Upon successful completion, re_exec() returns 1 if string matches the
last compiled regular expression. Otherwise, re_exec() returns 0 if
string fails to match the last compiled regular expression, and -1 if
the compiled regular expression is invalid (indicating an internal
error).
No errors are defined.
For portability to implementations conforming to X/Open standards
prior to SUS, regcomp(3C) and regexec(3C) are preferred to these
functions. See standards(7).
grep(1), regcmp(1), regcmp(3C), regcomp(3C), regexec(3C),
regexpr(3GEN), regexp(7), standards(7)
February 26, 1997 RE_COMP(3C)
NAME
re_comp, re_exec - compile and execute regular expressions
SYNOPSIS
#include <re_comp.h>
char *re_comp(const char *string);
int re_exec(const char *string);
DESCRIPTION
The re_comp() function converts a regular expression string (RE) into
an internal form suitable for pattern matching. The re_exec()
function compares the string pointed to by the string argument with
the last regular expression passed to re_comp().
If re_comp() is called with a null pointer argument, the current
regular expression remains unchanged.
Strings passed to both re_comp() and re_exec() must be terminated by
a null byte, and may include NEWLINE characters.
The re_comp() and re_exec() functions support simple regular
expressions, which are defined on the regexp(7) manual page. The
regular expressions of the form \{m\}, \{m,\}, or \{m,n\} are not
supported.
RETURN VALUES
The re_comp() function returns a null pointer when the string pointed
to by the string argument is successfully converted. Otherwise, a
pointer to one of the following error message strings is returned:
No previous regular expression
Regular expression too long
unmatched \(
missing ]
too many \(\) pairs
unmatched \)
Upon successful completion, re_exec() returns 1 if string matches the
last compiled regular expression. Otherwise, re_exec() returns 0 if
string fails to match the last compiled regular expression, and -1 if
the compiled regular expression is invalid (indicating an internal
error).
ERRORS
No errors are defined.
USAGE
For portability to implementations conforming to X/Open standards
prior to SUS, regcomp(3C) and regexec(3C) are preferred to these
functions. See standards(7).
SEE ALSO
grep(1), regcmp(1), regcmp(3C), regcomp(3C), regexec(3C),
regexpr(3GEN), regexp(7), standards(7)
February 26, 1997 RE_COMP(3C)