Content-type: text/html Man page of regex.h


Section: Headers (3HEAD)
Updated: 9 Sep 2004
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regex.h, regex - regular expression matching types  


#include <regex.h>


The <regex.h> header defines the structures and symbolic constants used by the regcomp(), regexec(), regerror(), and regfree() functions. See regcomp(3C).

The structure type regex_t contains the following member:

size_t re_nsub     number of parenthesized subexpressions

The type size_t is defined as described in <sys/types.h>. See types.h(3HEAD).

The type regoff_t is defined as a signed integer type that can hold the largest value that can be stored in either a type off_t or type ssize_t. The structure type regmatch_t contains the following members:

regoff_t rm_so     byte offset from start of string to start of substring
regoff_t rm_eo     byte offset from start of string of the first character after the end
                   of substring

Values for the cflags parameter to the regcomp function are as follows:

REG_EXTENDED use extended regular expressions

REG_ICASE ignore case in match

REG_NOSUB report only success or fail in regexec()

REG_NEWLINE change the handling of NEWLINE character

Values for the eflags parameter to the regexec() function are as follows:

REG_NOTBOL The circumflex character (^), when taken as a special character, does not match the beginning of string.

REG_NOTEOL The dollar sign ($), when taken as a special character, does not match the end of string.

The following constants are defined as error return values:

REG_NOMATCH regexec() failed to match.

REG_BADPAT Invalid regular expression.

REG_ECOLLATE Invalid collating element referenced.

REG_ECTYPE Invalid character class type referenced.

REG_EESCAPE Trailing '\' in pattern.

REG_ESUBREG Number in \fIdigit invalid or in error.

REG_EBRACK "[]" imbalance.

REG_EPAREN "\(\)" or "()" imbalance.

REG_EBRACE "" imbalance.

REG_BADBR Content of "" invalid: not a number, number too large, more than two numbers, first larger than second.

REG_ERANGE Invalid endpoint in range expression.

REG_ESPACE Out of memory.

REG_BADRPT '?', '*', or '+' not preceded by valid regular expression.

REG_ENOSYS Reserved.



See attributes(5) for descriptions of the following attributes:

Interface StabilityStandard



regcomp(3C), types.h(3HEAD), attributes(5), standards(5)




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Time: 02:37:12 GMT, October 02, 2010