.TH PCRE2_SET_CALLOUT 3 "21 March 2017" "PCRE2 10.30" .SH NAME PCRE2 - Perl-compatible regular expressions (revised API) .SH SYNOPSIS .rs .sp .B #include .PP .nf .B int pcre2_set_callout(pcre2_match_context *\fImcontext\fP, .B " int (*\fIcallout_function\fP)(pcre2_callout_block *)," .B " void *\fIcallout_data\fP);" .fi . .SH DESCRIPTION .rs .sp This function sets the callout fields in a match context (the first argument). The second argument specifies a callout function, and the third argument is an opaque data item that is passed to it. The result of this function is always zero. .P 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.