github/doc/pcre2_match.3

.TH PCRE2_MATCH 3 "27 January 2024" "PCRE2 10.43"
.SH NAME
PCRE2 - Perl-compatible regular expressions (revised API)
.SH SYNOPSIS
.rs
.sp
.B #include <pcre2.h>
.PP
.nf
.B int pcre2_match(const pcre2_code *\fIcode\fP, PCRE2_SPTR \fIsubject\fP,
.B "  PCRE2_SIZE \fIlength\fP, PCRE2_SIZE \fIstartoffset\fP,"
.B "  uint32_t \fIoptions\fP, pcre2_match_data *\fImatch_data\fP,"
.B "  pcre2_match_context *\fImcontext\fP);"
.fi
.
.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 what it has matched and to captured substrings via the
\fBmatch_data\fP block, which can be processed by functions with names that
start with \fBpcre2_get_ovector_...()\fP or \fBpcre2_substring_...()\fP. The
return from \fBpcre2_match()\fP is one more than the highest numbered capturing
pair that has been set (for example, 1 if there are no captures), zero if the
vector of offsets is too small, or a negative error code for no match and other
errors. The function arguments are:
.sp
  \fIcode\fP         Points to the compiled pattern
  \fIsubject\fP      Points to the subject string
  \fIlength\fP       Length of the subject string
  \fIstartoffset\fP  Offset in the subject at which to start matching
  \fIoptions\fP      Option bits
  \fImatch_data\fP   Points to a match data block, for results
  \fImcontext\fP     Points to a match context, or is NULL
.sp
A match context is needed only if you want to:
.sp
  Set up a callout function
  Set a matching offset limit
  Change the heap memory limit
  Change the backtracking match limit
  Change the backtracking depth limit
  Set custom memory management specifically for the match
.sp
The \fIlength\fP and \fIstartoffset\fP values are code units, not characters.
The length may be given as PCRE2_ZERO_TERMINATED for a subject that is
terminated by a binary zero code unit. The options are:
.sp
  PCRE2_ANCHORED          Match only at the first position
  PCRE2_COPY_MATCHED_SUBJECT
                          On success, make a private subject copy
  PCRE2_DISABLE_RECURSELOOP_CHECK
                          Only useful in rare cases; use with care
  PCRE2_ENDANCHORED       Pattern can match only at end of subject
  PCRE2_NOTBOL            Subject string is not the beginning of a line
  PCRE2_NOTEOL            Subject string is not the end of a line
  PCRE2_NOTEMPTY          An empty string is not a valid match
.\" JOIN
  PCRE2_NOTEMPTY_ATSTART  An empty string at the start of the subject
                           is not a valid match
  PCRE2_NO_JIT            Do not use JIT matching
.\" JOIN
  PCRE2_NO_UTF_CHECK      Do not check the subject for UTF
                           validity (only relevant if PCRE2_UTF
                           was set at compile time)
.\" JOIN
  PCRE2_PARTIAL_HARD      Return PCRE2_ERROR_PARTIAL for a partial
                           match even if there is a full match
.\" JOIN
  PCRE2_PARTIAL_SOFT      Return PCRE2_ERROR_PARTIAL for a partial
                           match if no full matches are found
.sp
For details of partial matching, see the
.\" HREF
\fBpcre2partial\fP
.\"
page. There is a complete description of the PCRE2 native API in the
.\" HREF
\fBpcre2api\fP
.\"
page and a description of the POSIX API in the
.\" HREF
\fBpcre2posix\fP
.\"
page.