+ if (!strcmp("-f", arg)) {
+ FILE *patterns;
+ int lno = 0;
+ char buf[1024];
+ if (argc <= 1)
+ usage(builtin_grep_usage);
+ patterns = fopen(argv[1], "r");
+ if (!patterns)
+ die("'%s': %s", argv[1], strerror(errno));
+ while (fgets(buf, sizeof(buf), patterns)) {
+ int len = strlen(buf);
+ if (buf[len-1] == '\n')
+ buf[len-1] = 0;
+ /* ignore empty line like grep does */
+ if (!buf[0])
+ continue;
+ add_pattern(&opt, strdup(buf), argv[1], ++lno);
+ }
+ fclose(patterns);
+ argv++;
+ argc--;
+ continue;
+ }