.TH PCRE_EXEC 3
.SH NAME
PCRE - Perl-compatible regular expressions
.SH SYNOPSIS
.rs
.sp
.B #include <pcre.h>
.PP
.SM
.B int pcre_exec(const pcre *\fIcode\fP, "const pcre_extra *\fIextra\fP,"
.ti +5n
.B "const char *\fIsubject\fP," int \fIlength\fP, int \fIstartoffset\fP,
.ti +5n
.B int \fIoptions\fP, int *\fIovector\fP, int \fIovecsize\fP);
.
.SH DESCRIPTION
.rs
.sp
This function matches a compiled regular expression against a given subject
string, using a matching algorithm that is similar to Perl's. It returns
offsets to captured substrings. Its arguments are:
.sp
  \fIcode\fP         Points to the compiled pattern
  \fIextra\fP        Points to an associated \fBpcre_extra\fP structure,
                 or is NULL
  \fIsubject\fP      Points to the subject string
  \fIlength\fP       Length of the subject string, in bytes
  \fIstartoffset\fP  Offset in bytes in the subject at which to
                 start matching
  \fIoptions\fP      Option bits
  \fIovector\fP      Points to a vector of ints for result offsets
  \fIovecsize\fP     Number of elements in the vector (a multiple of 3)
.sp
The options are:
.sp
  PCRE_ANCHORED          Match only at the first position
  PCRE_BSR_ANYCRLF       \eR matches only CR, LF, or CRLF
  PCRE_BSR_UNICODE       \eR matches all Unicode line endings
  PCRE_NEWLINE_ANY       Recognize any Unicode newline sequence
  PCRE_NEWLINE_ANYCRLF   Recognize CR, LF, & CRLF as newline sequences
  PCRE_NEWLINE_CR        Recognize CR as the only newline sequence
  PCRE_NEWLINE_CRLF      Recognize CRLF as the only newline sequence
  PCRE_NEWLINE_LF        Recognize LF as the only newline sequence
  PCRE_NOTBOL            Subject string is not the beginning of a line
  PCRE_NOTEOL            Subject string is not the end of a line
  PCRE_NOTEMPTY          An empty string is not a valid match
  PCRE_NOTEMPTY_ATSTART  An empty string at the start of the subject
                           is not a valid match
  PCRE_NO_START_OPTIMIZE Do not do "start-match" optimizations
  PCRE_NO_UTF8_CHECK     Do not check the subject for UTF-8
                           validity (only relevant if PCRE_UTF8
                           was set at compile time)
  PCRE_PARTIAL           ) Return PCRE_ERROR_PARTIAL for a partial
  PCRE_PARTIAL_SOFT      )   match if no full matches are found
  PCRE_PARTIAL_HARD      Return PCRE_ERROR_PARTIAL for a partial match
                           even if there is a full match as well
.sp
For details of partial matching, see the
.\" HREF
\fBpcrepartial\fP
.\"
page. A \fBpcre_extra\fP structure contains the following fields:
.sp
  \fIflags\fP        Bits indicating which fields are set
  \fIstudy_data\fP   Opaque data from \fBpcre_study()\fP
  \fImatch_limit\fP  Limit on internal resource use
  \fImatch_limit_recursion\fP  Limit on internal recursion depth
  \fIcallout_data\fP Opaque data passed back to callouts
  \fItables\fP       Points to character tables or is NULL
.sp
The flag bits are PCRE_EXTRA_STUDY_DATA, PCRE_EXTRA_MATCH_LIMIT,
PCRE_EXTRA_MATCH_LIMIT_RECURSION, PCRE_EXTRA_CALLOUT_DATA, and
PCRE_EXTRA_TABLES.
.P
There is a complete description of the PCRE native API in the
.\" HREF
\fBpcreapi\fP
.\"
page and a description of the POSIX API in the
.\" HREF
\fBpcreposix\fP
.\"
page.