Fixed bug in example.

This closes SF bug #415522.

Also fix markup error in text following the example.

Doc/lib/libfcntl.tex

@@ -106,13 +106,13 @@ Examples (all on a SVR4 compliant system):
 import struct, fcntl, FCNTL
 
 file = open(...)
-rv = fcntl(file.fileno(), FCNTL.O_NDELAY, 1)
+rv = fcntl(file.fileno(), FCNTL.F_SETFL, FCNTL.O_NDELAY)
 
 lockdata = struct.pack('hhllhh', FCNTL.F_WRLCK, 0, 0, 0, 0, 0)
 rv = fcntl.fcntl(file.fileno(), FCNTL.F_SETLKW, lockdata)
 \end{verbatim}
 
-Note that in the first example the return value variable \code{rv} will
+Note that in the first example the return value variable \var{rv} will
 hold an integer value; in the second example it will hold a string
 value.  The structure lay-out for the \var{lockdata} variable is
 system dependent --- therefore using the \function{flock()} call may be