REGEX.H(3HEAD) Headers REGEX.H(3HEAD)

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 digit 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(7) for descriptions of the following attributes:

ATTRIBUTE TYPE ATTRIBUTE VALUE
Interface Stability Standard

regcomp(3C), types.h(3HEAD), attributes(7), standards(7)

September 9, 2004 OmniOS