ap_pregsub — substitute for regular-expression submatches
char *ap_pregsub(pool *p, const char *input, const char *source, size_t nmatch, regmatch_t pmatch[])
Substitutes for $0-$9 in input,
using source as the source of the substitutions
and pmatch to determine from where to substitute.
nmatch, pmatch, and
source should be the same as passed to
regexec(). Returns the substituted version of
input in memory allocated from
p.