PCRE2_SUBSTITUTE(3)    FreeBSD Library Functions Manual    PCRE2_SUBSTITUTE(3)

NAME
       PCRE2 - Perl-compatible regular expressions (revised API)

SYNOPSIS
       #include <pcre2.h>

       int pcre2_substitute(const pcre2_code *code, PCRE2_SPTR subject,
         PCRE2_SIZE length, PCRE2_SIZE startoffset,
         uint32_t options, pcre2_match_data *match_data,
         pcre2_match_context *mcontext, PCRE2_SPTR replacement,
         PCRE2_SIZE rlength, PCRE2_UCHAR *outputbuffer,
         PCRE2_SIZE *outlengthptr);

DESCRIPTION
       This function matches a compiled regular expression against a given
       subject string, using a matching algorithm that is similar to Perl's.
       It then makes a copy of the subject, substituting a replacement string
       for what was matched.  Its arguments are:

         code          Points to the compiled pattern
         subject       Points to the subject string
         length        Length of the subject string
         startoffset   Offset in the subject at which to start matching
         options       Option bits
         match_data    Points to a match data block, or is NULL
         mcontext      Points to a match context, or is NULL
         replacement   Points to the replacement string
         rlength       Length of the replacement string
         outputbuffer  Points to the output buffer
         outlengthptr  Points to the length of the output buffer

       A match data block is needed only if you want to inspect the data from
       the final match that is returned in that block or if
       PCRE2_SUBSTITUTE_MATCHED is set. A match context is needed only if you
       want to:

         Set up a callout function
         Set a matching offset limit
         Change the backtracking match limit
         Change the backtracking depth limit
         Set custom memory management in the match context

       The length, startoffset and rlength values are code units, not
       characters, as is the contents of the variable pointed at by
       outlengthptr. This variable must contain the length of the output
       buffer when the function is called. If the function is successful, the
       value is changed to the length of the new string, excluding the
       trailing zero that is automatically added.

       The subject and replacement lengths can be given as
       PCRE2_ZERO_TERMINATED for zero-terminated strings. The options are:

         PCRE2_ANCHORED             Match only at the first position
         PCRE2_ENDANCHORED          Pattern can match only at end of subject
         PCRE2_NOTBOL               Subject is not the beginning of a line
         PCRE2_NOTEOL               Subject is not the end of a line
         PCRE2_NOTEMPTY             An empty string is not a valid match
         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
         PCRE2_NO_UTF_CHECK         Do not check the subject or replacement
                                     for UTF validity (only relevant if
                                     PCRE2_UTF was set at compile time)
         PCRE2_SUBSTITUTE_EXTENDED  Do extended replacement processing
         PCRE2_SUBSTITUTE_GLOBAL    Replace all occurrences in the subject
         PCRE2_SUBSTITUTE_LITERAL   The replacement string is literal
         PCRE2_SUBSTITUTE_MATCHED   Use pre-existing match data for 1st match
         PCRE2_SUBSTITUTE_OVERFLOW_LENGTH  If overflow, compute needed length
         PCRE2_SUBSTITUTE_REPLACEMENT_ONLY  Return only replacement string(s)
         PCRE2_SUBSTITUTE_UNKNOWN_UNSET  Treat unknown group as unset
         PCRE2_SUBSTITUTE_UNSET_EMPTY  Simple unset insert = empty string

       If PCRE2_SUBSTITUTE_LITERAL is set, PCRE2_SUBSTITUTE_EXTENDED,
       PCRE2_SUBSTITUTE_UNKNOWN_UNSET, and PCRE2_SUBSTITUTE_UNSET_EMPTY are
       ignored.

       If PCRE2_SUBSTITUTE_MATCHED is set, match_data must be non-zero; its
       contents must be the result of a call to pcre2_match() using the same
       pattern and subject.

       The function returns the number of substitutions, which may be zero if
       there are no matches. The result may be greater than one only when
       PCRE2_SUBSTITUTE_GLOBAL is set. In the event of an error, a negative
       error code is returned.

       There is a complete description of the PCRE2 native API in the pcre2api
       page and a description of the POSIX API in the pcre2posix page.

PCRE2 10.35                     22 January 2020            PCRE2_SUBSTITUTE(3)