Removed submodules

p1-sh/utils/head.c

@@ -0,0 +1,58 @@
+#define _GNU_SOURCE
+#include <stdbool.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+
+// You may assume that lines are no longer than 1024 bytes
+#define LINELEN 1024
+
+static void usage (void) __attribute__ ((unused));
+
+int
+main (int argc, char *argv[])
+{
+  int opt;
+  int n = 5;
+
+  while ((opt = getopt (argc, argv, "n:")) != -1)
+    {
+      switch (opt)
+        {
+        case 'n':
+          n = strtol (optarg, NULL, 10);
+          break;
+        default:
+          printf ("./bin/head: invalid option -- \'%c\'\n", optopt);
+          exit (EXIT_FAILURE);
+        }
+    }
+
+  FILE *file = optind < argc ? fopen (argv[optind], "r") : stdin;
+  if (file == NULL)
+    {
+      perror ("Failed to open input file");
+      exit (EXIT_FAILURE);
+    }
+
+  char buffer[LINELEN];
+  int count = 0;
+
+  while (count < n && fgets (buffer, sizeof (buffer), file) != NULL)
+    {
+      printf ("%s", buffer);
+      count++;
+    }
+
+  return EXIT_SUCCESS;
+}
+
+static void
+usage (void)
+{
+  printf ("head, prints the first few lines of a file\n");
+  printf ("usage: head [FLAG] FILE\n");
+  printf ("FLAG can be:\n");
+  printf ("  -n N     show the first N lines (default 5)\n");
+  printf ("If no FILE specified, read from STDIN\n");
+}