+IV
+PerlIOUnix_seek(pTHX_ PerlIO *f, Off_t offset, int whence)
+{
+ int fd = PerlIOSelf(f, PerlIOUnix)->fd;
+ Off_t new;
+ if (PerlIOBase(f)->flags & PERLIO_F_NOTREG) {
+#ifdef ESPIPE
+ SETERRNO(ESPIPE, LIB_INVARG);
+#else
+ SETERRNO(EINVAL, LIB_INVARG);
+#endif
+ return -1;
+ }
+ new = PerlLIO_lseek(fd, offset, whence);
+ if (new == (Off_t) - 1)
+ {
+ return -1;
+ }
+ PerlIOBase(f)->flags &= ~PERLIO_F_EOF;
+ return 0;
+}
+