Returns true if the named file has the setuid bit set.
/*
* call-seq:
* File.setuid?(file_name) => true or false
*
* Returns <code>true</code> if the named file has the setuid bit set.
*/
static VALUE
test_suid(obj, fname)
VALUE obj, fname;
{
#ifdef S_ISUID
return check3rdbyte(fname, S_ISUID);
#else
return Qfalse;
#endif
}