pipe?

/*
 * call-seq:
 *   File.pipe?(file_name)   =>  true or false
 *
 * Returns <code>true</code> if the named file is a pipe.
 */

static VALUE
test_p(obj, fname)
    VALUE obj, fname;
{
#ifdef S_IFIFO
#  ifndef S_ISFIFO
#    define S_ISFIFO(m) ((m & S_IFMT) == S_IFIFO)
#  endif

    struct stat st;

    if (rb_stat(fname, &st) < 0) return Qfalse;
    if (S_ISFIFO(st.st_mode)) return Qtrue;

#endif
    return Qfalse;
}