should be left unchanged if an entry is not found.
Experiments on various
UNIX-like systems show that lots of different values occur in this
-situation: 0, ENOENT, EBADF, ESRCH, EWOULDBLOCK, EPERM and probably others.
+situation: 0, ENOENT, EBADF, ESRCH, EWOULDBLOCK, EPERM, and probably others.
.\" more precisely:
.\" AIX 5.1 - gives ESRCH
.\" OSF1 4.0g - gives EWOULDBLOCK