+
+static const char *usage = "Usage: %s [options] [hostname] [port]\n"
+ "Options:\n"
+ " -h: print usage information and exit\n";
+
+int parse_args(int argc, char **argv)
+{
+ int i, argidx = 0;
+
+ for(i=1; i<argc; i++) {
+ if(argv[i][0] == '-') {
+ if(argv[i][2] != 0) {
+ goto inval;
+ }
+ switch(argv[i][1]) {
+ case 'h':
+ printf(usage, argv[0]);
+ exit(0);
+
+ default:
+ goto inval;
+ }
+
+ } else {
+ switch(argidx++) {
+ case 0:
+ host = argv[i];
+ break;
+
+ case 1:
+ if((port = atoi(argv[i])) <= 0) {
+ fprintf(stderr, "invalid port number: %s\n", argv[i]);
+ return -1;
+ }
+ break;
+
+ default:
+ goto inval;
+ }
+ }
+ }
+
+ return 0;
+inval:
+ fprintf(stderr, "invalid argument: %s\n", argv[i]);
+ fprintf(stderr, usage, argv[0]);
+ return -1;
+}