From b79fe9ac803a07f845f05f042a2dcab0efb859cc Mon Sep 17 00:00:00 2001 From: Jakob Kaivo Date: Wed, 13 Mar 2019 21:30:58 -0400 Subject: migrate to gitlab --- head.c | 95 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 95 insertions(+) create mode 100644 head.c diff --git a/head.c b/head.c new file mode 100644 index 0000000..59e53f6 --- /dev/null +++ b/head.c @@ -0,0 +1,95 @@ +/* + * UNG's Not GNU + * + * Copyright (c) 2011-2017, Jakob Kaivo + * + * Permission to use, copy, modify, and/or distribute this software for any + * purpose with or without fee is hereby granted, provided that the above + * copyright notice and this permission notice appear in all copies. + * + * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES + * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF + * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR + * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES + * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN + * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF + * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. + * + */ + +#define _XOPEN_SOURCE 700 +#include +#include +#include +#include +#include + +static int head(const char *path, int nlines) +{ + FILE *f = stdin; + if (path && strcmp(path, "-")) { + f = fopen(path, "rb"); + } + + if (f == NULL) { + fprintf(stderr, "FIXME: Couldn't open %s: %s\n", path ? path : "stdin", strerror(errno)); + return 1; + } + + while (!feof(f) && nlines > 0) { + char *line = NULL; + size_t n = 0; + + getline(&line, &n, f); + fputs(line, stdout); + nlines--; + } + + if (f != stdin) { + fclose(f); + } + + return 0; +} + +int main(int argc, char **argv) +{ + int lines = 10; + int showname = 0; + char *end; + + int c; + while ((c = getopt(argc, argv, ":n:")) != -1) { + switch (c) { + case 'n': + lines = strtol(optarg, &end, 10); + if (end != NULL && strlen(end) > 0) { + fprintf(stderr, "head: Invalid number %s\n", optarg); + return 1; + } + break; + + default: + return 1; + } + } + + if (optind < argc - 1) { + showname = 1; + } + + int r = 0; + do { + if (showname) { + if (showname == 1) { + showname++; + } else { + putchar('\n'); + } + printf("==> %s <==\n", argv[optind]); + } + r |= head(argv[optind++], lines); + } while (optind < argc); + + return r; +} -- cgit v1.2.1