\fIs1\fR, ignoring case. Returns NULL if
\fIs2\fR is not present in \fIs1\fR\&.
This test is case-insensitive for all proper UTF-8 encoded strings.
\fIs1\fR, ignoring case. Returns NULL if
\fIs2\fR is not present in \fIs1\fR\&.
This test is case-insensitive for all proper UTF-8 encoded strings.