swab \- swap adjacent bytes
.SH SYNOPSIS
.nf
-.B #define _XOPEN_SOURCE
+.BR "#define _XOPEN_SOURCE" " /* See feature_test_macros(7) */"
.B #include <unistd.h>
.sp
.BI "void swab(const void *" from ", void *" to ", ssize_t " n );
.SH "CONFORMING TO"
SVr4, 4.3BSD, POSIX.1-2001.
.SH "SEE ALSO"
-.BR bstring (3),
-.BR feature_test_macros (7)
+.BR bstring (3)