apps/app.c

@@ -15,20 +15,23 @@ int main()
     atexit(bye);
     printf("Welcome to %s from userspace (pid %d)!\n", "Luna", getpid());
 
-    FILE* f = fopen("/etc/motd", "r");
-    if (!f)
+    mkdir("/home", 0755);
+    mkdir("/home/user", 0755);
+
+    int fd = open("/home/user/notes.txt", O_RDWR | O_CREAT, 0644);
+    if (fd < 0)
     {
-        perror("fopen");
+        perror("open");
         return 1;
     }
 
     char buffer[512];
-    size_t nread = fread(buffer, 1, sizeof(buffer), f);
+    ssize_t nread = read(fd, buffer, sizeof(buffer));
     buffer[nread] = 0;
 
-    printf("/etc/motd says: %s", buffer);
+    printf("/home/user/notes.txt says: %s", buffer);
 
-    fclose(f);
+    close(fd);
 
     time_t now = time(NULL);
     printf("date: %s", ctime(&now));

libc/src/stdio.cpp

@@ -10,23 +10,6 @@
 
 FILE* stderr = nullptr;
 
-static int fopen_parse_mode(const char* mode)
-{
-    int result = 0;
-    switch (*mode)
-    {
-    case 'r': result |= O_RDONLY; break;
-    case 'w': result |= (O_WRONLY | O_CREAT | O_TRUNC); break;
-    case 'a': result |= (O_WRONLY | O_CREAT | O_APPEND); break;
-
-    default: errno = EINVAL; return -1;
-    }
-
-    if (strchr(mode, '+')) result |= O_RDWR;
-
-    return result;
-}
-
 extern "C"
 {
     int console_write(const char* str, size_t size)
@@ -35,13 +18,10 @@ extern "C"
         __errno_return(rc, int);
     }
 
-    FILE* fopen(const char* path, const char* mode)
+    FILE* fopen(const char* path, const char*)
     {
-        int flags;
-
-        if ((flags = fopen_parse_mode(mode)) < 0) return nullptr;
-
-        int fd = open(path, flags, 0666);
+        // FIXME: Parse the mode string.
+        int fd = open(path, O_RDWR);
         if (fd < 0) return nullptr;
 
         FILE* f = (FILE*)malloc(sizeof(FILE));