re_comp()
Compile a regular expression
Synopsis:
#include <unix.h>
char *re_comp( char *s );
Arguments:
- s
- A string that contains the regular expression that you want to compile. This string must end with a null byte and may include newline characters. If this argument is NULL, the current regular expression remains unchanged.
Library:
libc
Use the -l c option to qcc to link against this library. This library is usually included automatically.
Description:
The re_comp() function converts a regular expression string (RE) into an internal form suitable for pattern matching. Use this function with re_exec() .
The re_comp() and re_exec() functions support simple regular expressions. The regular expressions of the form \{m\}, \{m,\}, or \{m,n\} aren't supported.
Returns:
NULL if the string pointed to by s was 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 \)
Classification:
Safety: | |
---|---|
Cancellation point | No |
Interrupt handler | No |
Signal handler | Yes |
Thread | Yes |