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.TH regex_t 3type 2022-10-30 "Linux man-pages 6.03"
.SH NAME
regex_t, regmatch_t, regoff_t
\- regular expression matching
.SH LIBRARY
Standard C library
.RI ( libc )
.SH SYNOPSIS
.EX
.B #include <regex.h>
.PP
.B typedef struct {
.BR "    size_t    re_nsub;" "  /* Number of parenthesized subexpressions */"
.B } regex_t;
.PP
.B typedef struct {
.BR "    regoff_t  rm_so;" "    /* Byte offset from start of string"
                           to start of substring */
.BR "    regoff_t  rm_eo;" "    /* Byte offset from start of string to"
                           the first character after the end of
                           substring */
.B } regmatch_t;
.PP
.BR typedef " /* ... */  " regoff_t;
.EE
.SH DESCRIPTION
.TP
.I regex_t
This is a structure type used in regular expression matching.
It holds a compiled regular expression,
compiled with
.BR regcomp (3).
.TP
.I regmatch_t
This is a structure type used in regular expression matching.
.TP
.I regoff_t
It is a signed integer type
capable of storing the largest value that can be stored in either an
.I ptrdiff_t
type or a
.I ssize_t
type.
.SH VERSIONS
Prior to POSIX.1-2008,
the type was
capable of storing the largest value that can be stored in either an
.I off_t
type or a
.I ssize_t
type.
.SH STANDARDS
POSIX.1-2001 and later.
.SH SEE ALSO
.BR regex (3)