Bokens exempelprogram

2019-03-29 05:43:54 +01:00
commit 9fd3ac4a26
10 changed files with 719 additions and 0 deletions
--- a/simple-ls-ver2.c
+++ b/simple-ls-ver2.c
@@ -0,0 +1,75 @@
+#define _XOPEN_SOURCE 500
+#include <stdio.h>
+#include <dirent.h>
+#include <unistd.h>
+#include <sys/stat.h>
+
+void printUsage(char *arg);
+
+int main(int argc, char **argv)
+{
+    int opt;
+    int typ = -1;
+    char *path = ".";
+    
+    /* Skapa pekare och struct */
+    DIR           *d;
+    struct dirent *dir;
+    struct stat s;
+    
+    /* Behandla argument med getopt */
+    while ((opt = getopt(argc, argv, "hafdp:")) != -1)
+    {
+        switch (opt)
+        {
+        case 'a':
+            typ = -1;
+            break;
+        case 'f':
+            typ = S_IFREG;
+            break;
+        case 'd':
+            typ = S_IFDIR;
+            break;
+        case 'p':
+            path = optarg;
+            break;
+        case 'h':
+            printUsage(argv[0]);
+            return 0;
+        default:
+            printUsage(argv[0]);
+            return 1;
+        }
+    }
+
+    /* Byt katalog med chdir() för att stat() ska
+       se filerna i rätt katalog */
+    chdir(path);
+
+    d = opendir(path);
+    while ((dir = readdir(d)) != NULL)
+    {
+        if ( typ == -1 )
+        {
+            printf("%s\n", dir->d_name);
+        }
+        else
+        {
+            stat(dir->d_name, &s);
+            /* Se kapitlet om 'Bitvisa operationer' */
+            if ((s.st_mode & S_IFMT) == typ)
+                printf("%s\n", dir->d_name);
+        }
+    }
+        return 0;
+}
+
+void printUsage(char *arg)
+{
+    printf("Usage: %s [-a] [-f] [-d] [-p path]\n"
+           "    -a to list all types (default)\n"
+           "    -f to list only files\n"
+           "    -d to list only directories\n"
+           "    -p to specify a directory\n", arg);
+}