Get option character from command line
#include <sgetopt.h>
The sgetopt library is just like the getopt library, except that it prints errors using substdio rather than stdio.
See getopt(3) for interface details.
sgetopt version 1.9, 931201.
Placed into the public domain by Daniel J. Bernstein.
getopt(3), subgetopt(3), subfd(3), substdio(3)