fix(vfs): resolve CWD tracking, filename clobbering, touch creation, and nano full-screen editing & saving

fs/vfs.c

@@ -10,9 +10,11 @@
 
 static vfs_node_t* vfs_root = NULL;
 static file_descriptor_t file_descriptors[MAX_OPEN_FILES];
+static char vfs_cwd[256] = "/";
 
 void vfs_init(void) {
     memset(file_descriptors, 0, sizeof(file_descriptors));
+    strcpy(vfs_cwd, "/");
 
     // 1. Create root RAM filesystem
     vfs_root = ramfs_create_root();
@@ -32,14 +34,104 @@ vfs_node_t* vfs_get_root(void) {
     return vfs_root;
 }
 
+const char* vfs_getcwd(void) {
+    return vfs_cwd;
+}
+
+void vfs_resolve_path(const char* path, char* resolved_out, size_t max_len) {
+    if (!resolved_out || max_len == 0) return;
+
+    char temp[512];
+    if (!path || path[0] == '\0') {
+        strncpy(resolved_out, vfs_cwd, max_len - 1);
+        resolved_out[max_len - 1] = '\0';
+        return;
+    }
+
+    if (path[0] == '/') {
+        strncpy(temp, path, sizeof(temp) - 1);
+    } else {
+        if (strcmp(vfs_cwd, "/") == 0) {
+            snprintf(temp, sizeof(temp), "/%s", path);
+        } else {
+            snprintf(temp, sizeof(temp), "%s/%s", vfs_cwd, path);
+        }
+    }
+    temp[sizeof(temp) - 1] = '\0';
+
+    // Normalize '.' and '..' components
+    char* stack[32];
+    int top = 0;
+
+    char* token = temp;
+    while (*token == '/') token++;
+
+    while (*token) {
+        char* next_slash = strchr(token, '/');
+        if (next_slash) *next_slash = '\0';
+
+        if (strcmp(token, ".") == 0 || token[0] == '\0') {
+            // Do nothing
+        } else if (strcmp(token, "..") == 0) {
+            if (top > 0) top--;
+        } else {
+            if (top < 32) {
+                stack[top++] = token;
+            }
+        }
+
+        if (next_slash) {
+            token = next_slash + 1;
+            while (*token == '/') token++;
+        } else {
+            break;
+        }
+    }
+
+    if (top == 0) {
+        strcpy(resolved_out, "/");
+        return;
+    }
+
+    resolved_out[0] = '\0';
+    for (int i = 0; i < top; i++) {
+        strcat(resolved_out, "/");
+        strcat(resolved_out, stack[i]);
+    }
+}
+
+int vfs_chdir(const char* path) {
+    if (!path || path[0] == '\0') return -1;
+
+    char abs_path[256];
+    vfs_resolve_path(path, abs_path, sizeof(abs_path));
+
+    vfs_node_t* node = vfs_namei(abs_path);
+    if (!node) {
+        return -1; // Directory does not exist
+    }
+
+    if (!(node->flags & FS_DIRECTORY)) {
+        return -2; // Not a directory
+    }
+
+    strncpy(vfs_cwd, abs_path, sizeof(vfs_cwd) - 1);
+    vfs_cwd[sizeof(vfs_cwd) - 1] = '\0';
+    return 0;
+}
+
 vfs_node_t* vfs_namei(const char* path) {
     if (!path || !vfs_root) return NULL;
-    if (strcmp(path, "/") == 0) return vfs_root;
 
-    if (*path == '/') path++; // Skip leading slash
+    char abs_path[256];
+    vfs_resolve_path(path, abs_path, sizeof(abs_path));
+
+    if (strcmp(abs_path, "/") == 0) return vfs_root;
 
     char buffer[256];
-    strncpy(buffer, path, sizeof(buffer) - 1);
+    const char* p = abs_path;
+    if (*p == '/') p++;
+    strncpy(buffer, p, sizeof(buffer) - 1);
     buffer[sizeof(buffer) - 1] = '\0';
 
     vfs_node_t* current = vfs_root;
@@ -65,6 +157,7 @@ vfs_node_t* vfs_namei(const char* path) {
 
         if (next_slash) {
             token = next_slash + 1;
+            while (*token == '/') token++;
         } else {
             break;
         }
@@ -74,26 +167,45 @@ vfs_node_t* vfs_namei(const char* path) {
 }
 
 int vfs_open(const char* path, uint32_t flags) {
-    vfs_node_t* node = vfs_namei(path);
+    if (!path) return -1;
+
+    char abs_path[256];
+    vfs_resolve_path(path, abs_path, sizeof(abs_path));
+
+    vfs_node_t* node = vfs_namei(abs_path);
     if (!node) {
         if (flags & O_CREAT) {
             // Find parent and create
             char parent_path[256];
-            strncpy(parent_path, path, sizeof(parent_path) - 1);
+            strncpy(parent_path, abs_path, sizeof(parent_path) - 1);
+            parent_path[sizeof(parent_path) - 1] = '\0';
+
             char* last_slash = strrchr(parent_path, '/');
             if (last_slash) {
+                char filename[128];
+                strncpy(filename, last_slash + 1, sizeof(filename) - 1);
+                filename[sizeof(filename) - 1] = '\0';
+
+                if (last_slash == parent_path) {
+                    parent_path[1] = '\0'; // Root "/"
+                } else {
                     *last_slash = '\0';
-                const char* filename = last_slash + 1;
-                vfs_node_t* parent = vfs_namei(parent_path[0] ? parent_path : "/");
+                }
+
+                vfs_node_t* parent = vfs_namei(parent_path);
                 if (parent && parent->create) {
                     parent->create(parent, filename, 0644);
-                    node = vfs_namei(path);
+                    node = vfs_namei(abs_path);
                 }
             }
         }
         if (!node) return -1;
     }
 
+    if (flags & O_TRUNC) {
+        node->length = 0;
+    }
+
     if (node->open) {
         if (node->open(node, flags) != 0) return -1;
     }
@@ -102,7 +214,7 @@ int vfs_open(const char* path, uint32_t flags) {
     for (int fd = 3; fd < MAX_OPEN_FILES; fd++) {
         if (!file_descriptors[fd].node) {
             file_descriptors[fd].node = node;
-            file_descriptors[fd].offset = 0;
+            file_descriptors[fd].offset = (flags & O_APPEND) ? (off_t)node->length : 0;
             file_descriptors[fd].flags = flags;
             return fd;
         }
@@ -160,100 +272,93 @@ off_t vfs_lseek(int fd, off_t offset, int whence) {
     if (fd < 0 || fd >= MAX_OPEN_FILES || !file_descriptors[fd].node) return -1;
 
     file_descriptor_t* desc = &file_descriptors[fd];
-    if (whence == SEEK_SET) desc->offset = offset;
-    else if (whence == SEEK_CUR) desc->offset += offset;
-    else if (whence == SEEK_END) desc->offset = desc->node->length + offset;
+    switch (whence) {
+        case SEEK_SET:
+            desc->offset = offset;
+            break;
+        case SEEK_CUR:
+            desc->offset += offset;
+            break;
+        case SEEK_END:
+            desc->offset = (off_t)desc->node->length + offset;
+            break;
+        default:
+            return -1;
+    }
     return desc->offset;
 }
 
 int vfs_close(int fd) {
     if (fd < 0 || fd >= MAX_OPEN_FILES || !file_descriptors[fd].node) return -1;
 
-    if (file_descriptors[fd].node->close) {
-        file_descriptors[fd].node->close(file_descriptors[fd].node);
+    file_descriptor_t* desc = &file_descriptors[fd];
+    if (desc->node->close) {
+        desc->node->close(desc->node);
     }
-    file_descriptors[fd].node = NULL;
-    file_descriptors[fd].offset = 0;
+
+    desc->node = NULL;
+    desc->offset = 0;
+    desc->flags = 0;
     return 0;
 }
 
 int vfs_mkdir(const char* path, mode_t mode) {
-    if (!path || !*path) return -1;
+    if (!path) return -1;
+
+    char abs_path[256];
+    vfs_resolve_path(path, abs_path, sizeof(abs_path));
+
     char parent_path[256];
-    strncpy(parent_path, path, sizeof(parent_path) - 1);
+    strncpy(parent_path, abs_path, sizeof(parent_path) - 1);
     parent_path[sizeof(parent_path) - 1] = '\0';
 
     char* last_slash = strrchr(parent_path, '/');
-    const char* dirname = path;
-    vfs_node_t* parent = vfs_get_root();
+    if (!last_slash) return -1;
+
+    char dirname[128];
+    strncpy(dirname, last_slash + 1, sizeof(dirname) - 1);
+    dirname[sizeof(dirname) - 1] = '\0';
 
-    if (last_slash) {
     if (last_slash == parent_path) {
-            parent = vfs_namei("/");
-            dirname = last_slash + 1;
+        parent_path[1] = '\0'; // Root "/"
     } else {
         *last_slash = '\0';
-            dirname = last_slash + 1;
-            parent = vfs_namei(parent_path);
-        }
     }
 
-    if (parent && parent->mkdir) {
+    vfs_node_t* parent = vfs_namei(parent_path);
+    if (!parent || !parent->mkdir) return -1;
+
     return parent->mkdir(parent, dirname, mode);
 }
-    return -1;
-}
 
 int vfs_create(const char* path, mode_t mode) {
-    if (!path || !*path) return -1;
-    char parent_path[256];
-    strncpy(parent_path, path, sizeof(parent_path) - 1);
-    parent_path[sizeof(parent_path) - 1] = '\0';
-
-    char* last_slash = strrchr(parent_path, '/');
-    const char* filename = path;
-    vfs_node_t* parent = vfs_get_root();
-
-    if (last_slash) {
-        if (last_slash == parent_path) {
-            parent = vfs_namei("/");
-            filename = last_slash + 1;
-        } else {
-            *last_slash = '\0';
-            filename = last_slash + 1;
-            parent = vfs_namei(parent_path);
-        }
-    }
-
-    if (parent && parent->create) {
-        return parent->create(parent, filename, mode);
-    }
-    return -1;
-}
-
-int vfs_mount(const char* path, vfs_node_t* fs_root) {
-    if (!path || !fs_root) return -1;
-    vfs_node_t* mount_node = vfs_namei(path);
-    if (!mount_node) {
-        // Create directory node for mount point
-        char parent_path[256];
-        strncpy(parent_path, path, sizeof(parent_path) - 1);
-        char* last_slash = strrchr(parent_path, '/');
-        if (last_slash) {
-            *last_slash = '\0';
-            const char* dirname = last_slash + 1;
-            vfs_node_t* parent = vfs_namei(parent_path[0] ? parent_path : "/");
-            if (parent && parent->mkdir) {
-                parent->mkdir(parent, dirname, 0755);
-                mount_node = vfs_namei(path);
-            }
-        }
-    }
-
-    if (mount_node) {
-        mount_node->flags |= FS_MOUNTPOINT;
-        mount_node->ptr = fs_root;
+    int fd = vfs_open(path, O_CREAT | O_RDWR);
+    if (fd >= 0) {
+        vfs_close(fd);
         return 0;
     }
     return -1;
 }
+
+int vfs_unlink(const char* path) {
+    (void)path;
+    return 0;
+}
+
+int vfs_mount(const char* path, vfs_node_t* fs_root) {
+    if (!path || !fs_root) return -1;
+
+    vfs_node_t* mountpoint = vfs_namei(path);
+    if (!mountpoint) {
+        // Automatically create directory if missing
+        if (vfs_mkdir(path, 0755) == 0) {
+            mountpoint = vfs_namei(path);
+        }
+    }
+
+    if (!mountpoint) return -1;
+
+    mountpoint->flags |= FS_MOUNTPOINT;
+    mountpoint->ptr = fs_root;
+    return 0;
+}

include/fs/vfs.h

@@ -82,5 +82,9 @@ int vfs_create(const char* path, mode_t mode);
 
 vfs_node_t* vfs_get_root(void);
 int vfs_mount(const char* path, vfs_node_t* fs_root);
+const char* vfs_getcwd(void);
+int vfs_chdir(const char* path);
+void vfs_resolve_path(const char* path, char* resolved_out, size_t max_len);
+int vfs_unlink(const char* path);
 
 #endif // _FS_VFS_H

userland/lazybox/lazybox.c

@@ -40,7 +40,7 @@
 // -------------------------------------------------------------
 
 static int applet_ls(int argc, char** argv) {
-    const char* path = (argc >= 2) ? argv[1] : "/";
+    const char* path = (argc >= 2) ? argv[1] : vfs_getcwd();
     vfs_node_t* dir = vfs_namei(path);
 
     if (!dir) {
@@ -112,6 +112,8 @@ static int applet_touch(int argc, char** argv) {
         int fd = vfs_open(argv[i], O_CREAT | O_RDWR);
         if (fd >= 0) {
             vfs_close(fd);
+        } else {
+            printk(KERN_ERR "touch: cannot touch '%s': No such file or directory\n", argv[i]);
         }
     }
     return 0;
@@ -141,14 +143,14 @@ static int applet_echo(int argc, char** argv) {
 
 static int applet_pwd(int argc, char** argv) {
     (void)argc; (void)argv;
-    printk("/\n");
+    printk("%s\n", vfs_getcwd());
     return 0;
 }
 
 static int applet_cd(int argc, char** argv) {
     const char* target = (argc >= 2) ? argv[1] : "/";
-    vfs_node_t* node = vfs_namei(target);
-    if (!node || !(node->flags & FS_DIRECTORY)) {
+    int res = vfs_chdir(target);
+    if (res != 0) {
         printk(KERN_ERR "cd: %s: No such file or directory\n", target);
         return 1;
     }

userland/lazybox/nano.c

@@ -16,39 +16,46 @@ static int nano_cursor_row = 0;
 static int nano_cursor_col = 0;
 static int nano_top_row = 0;
 static bool nano_modified = false;
-static char nano_filename[128];
-static char nano_status[80];
+static char nano_filename[256];
+static char nano_status[128];
 static char nano_cut_buffer[NANO_LINE_LEN];
 static bool nano_has_cut = false;
 
 static void nano_render(void) {
-    tty_clear();
-
-    // 1. Title bar (Inverted Color)
-    printk(ANSI_INVERT "  GNU nano 2.0.0             File: %-32s %s" ANSI_RESET "\n",
+    // 1. Title bar (Row 0)
+    tty_set_cursor(0, 0);
+    char title[128];
+    snprintf(title, sizeof(title), "  GNU nano 2.0.0             File: %-32s %s",
              nano_filename[0] ? nano_filename : "New Buffer",
              nano_modified ? "[Modified]" : "          ");
+    printk(ANSI_INVERT "%-80s" ANSI_RESET, title);
 
     // 2. Viewport Lines (Rows 1 to 21)
     for (int r = 0; r < NANO_SCREEN_ROWS; r++) {
+        tty_set_cursor(r + 1, 0);
         int line_idx = nano_top_row + r;
         if (line_idx < (int)nano_line_count) {
-            printk("%s\n", nano_lines[line_idx]);
+            printk("\033[K%s", nano_lines[line_idx]);
         } else {
-            printk("~\n");
+            printk("\033[K" ANSI_BRIGHT_BLACK "~" ANSI_RESET);
         }
     }
 
-    // 3. Status Message Bar
-    printk(ANSI_BRIGHT_CYAN "%-78s" ANSI_RESET "\n", nano_status);
+    // 3. Status Message Bar (Row 22)
+    tty_set_cursor(22, 0);
+    printk(ANSI_BRIGHT_CYAN "\033[K%-78s" ANSI_RESET, nano_status);
 
-    // 4. Shortcut Cheatsheet Footer
-    printk(ANSI_INVERT "^G Get Help  ^O WriteOut  ^W Where Is  ^K Cut Line  ^U Paste  ^X Exit" ANSI_RESET "\n");
+    // 4. Shortcut Cheatsheet Footer (Row 23)
+    tty_set_cursor(23, 0);
+    printk(ANSI_INVERT "%-80s" ANSI_RESET,
+           "^G Help   ^O WriteOut   ^W Where Is   ^K Cut Line   ^U Paste   ^X Exit");
 
     // 5. Position Hardware Cursor
-    int scr_row = (nano_cursor_row - nano_top_row) + 2;
-    int scr_col = nano_cursor_col + 1;
-    tty_set_cursor(scr_row - 1, scr_col - 1);
+    int scr_row = (nano_cursor_row - nano_top_row) + 1;
+    int scr_col = nano_cursor_col;
+    if (scr_row >= 1 && scr_row <= NANO_SCREEN_ROWS) {
+        tty_set_cursor(scr_row, scr_col);
+    }
 }
 
 static void nano_save(void) {
@@ -59,7 +66,7 @@ static void nano_save(void) {
 
     int fd = vfs_open(nano_filename, O_CREAT | O_WRONLY | O_TRUNC);
     if (fd < 0) {
-        strcpy(nano_status, "[ Error opening file for writing ]");
+        strcpy(nano_status, "[ Error: Cannot open file for writing ]");
         return;
     }
 
@@ -78,7 +85,7 @@ static void nano_save(void) {
     vfs_close(fd);
 
     nano_modified = false;
-    sprintf(nano_status, "[ Wrote %llu bytes to %s ]", (uint64_t)total_bytes, nano_filename);
+    snprintf(nano_status, sizeof(nano_status), "[ Wrote %llu bytes to %s ]", (uint64_t)total_bytes, nano_filename);
 }
 
 static void nano_load(const char* path) {
@@ -90,13 +97,21 @@ static void nano_load(const char* path) {
     nano_modified = false;
     nano_status[0] = '\0';
 
-    strncpy(nano_filename, path, sizeof(nano_filename) - 1);
+    if (!path || path[0] == '\0') {
+        nano_filename[0] = '\0';
+        nano_line_count = 1;
+        nano_lines[0][0] = '\0';
+        strcpy(nano_status, "[ New Buffer - Use ^O to save ]");
+        return;
+    }
 
-    int fd = vfs_open(path, O_RDONLY);
+    vfs_resolve_path(path, nano_filename, sizeof(nano_filename));
+
+    int fd = vfs_open(nano_filename, O_RDONLY);
     if (fd < 0) {
         nano_line_count = 1;
         nano_lines[0][0] = '\0';
-        sprintf(nano_status, "[ New File: %s ]", path);
+        snprintf(nano_status, sizeof(nano_status), "[ New File: %s ]", nano_filename);
         return;
     }
 
@@ -129,13 +144,14 @@ static void nano_load(const char* path) {
         cur_line++;
     }
     nano_line_count = cur_line > 0 ? cur_line : 1;
-    sprintf(nano_status, "[ Read %llu line(s) from %s ]", (uint64_t)nano_line_count, path);
+    snprintf(nano_status, sizeof(nano_status), "[ Read %llu line(s) from %s ]", (uint64_t)nano_line_count, nano_filename);
 }
 
 int nano_main(int argc, char** argv) {
+    tty_clear();
+
     if (argc < 2) {
         nano_load("");
-        strcpy(nano_status, "[ New Buffer - Use ^O to save ]");
     } else {
         nano_load(argv[1]);
     }
@@ -162,11 +178,16 @@ int nano_main(int argc, char** argv) {
         uint16_t key = keyboard_get_key();
 
         switch (key) {
-            case 0x18: // Ctrl+X -> Exit
+            case 0x18: // Ctrl+X
+            case 0x11: // Ctrl+Q
+            case 27:   // ESC
+            case KEY_F10:
                 running = false;
                 break;
 
-            case 0x0F: // Ctrl+O -> Write Out / Save
+            case 0x0F: // Ctrl+O
+            case 0x13: // Ctrl+S
+            case KEY_F2:
                 nano_save();
                 break;
 
@@ -200,6 +221,7 @@ int nano_main(int argc, char** argv) {
                 break;
 
             case 0x07: // Ctrl+G -> Help
+            case KEY_F1:
                 strcpy(nano_status, "[ Help: ^O=Save, ^X=Exit, ^K=Cut, ^U=Paste, Arrows=Move ]");
                 break;
 
@@ -250,7 +272,8 @@ int nano_main(int argc, char** argv) {
                                   nano_cursor_row + NANO_SCREEN_ROWS : (int)nano_line_count - 1;
                 break;
 
-            case '\n': // Enter -> Split line
+            case '\n':
+            case '\r': // Enter -> Split line
                 if (nano_line_count < NANO_MAX_LINES) {
                     for (int i = (int)nano_line_count; i > nano_cursor_row + 1; i--) {
                         strcpy(nano_lines[i], nano_lines[i - 1]);
@@ -286,6 +309,15 @@ int nano_main(int argc, char** argv) {
                 }
                 break;
 
+            case KEY_DELETE:
+                if (nano_cursor_col < line_len) {
+                    memmove(&nano_lines[nano_cursor_row][nano_cursor_col],
+                            &nano_lines[nano_cursor_row][nano_cursor_col + 1],
+                            strlen(&nano_lines[nano_cursor_row][nano_cursor_col + 1]) + 1);
+                    nano_modified = true;
+                }
+                break;
+
             default:
                 if (key >= 32 && key <= 126) {
                     char c = (char)key;

userland/lazybox/shell.c

@@ -1,5 +1,6 @@
 #include <userland/shell.h>
 #include <userland/lazybox.h>
+#include <fs/vfs.h>
 #include <drivers/tty.h>
 #include <drivers/keyboard.h>
 #include <drivers/speaker.h>
@@ -19,11 +20,14 @@ static int history_count = 0;
 static int history_head = 0;
 
 static const char* shell_builtins[] = {
-    "lazybox", "ls", "cat", "touch", "mkdir", "wc", "echo",
-    "md5sum", "sha256sum", "crc32", "ifconfig", "ping", "arp",
-    "hdparm", "uname", "free", "uptime", "dmesg", "sleep", "clear",
-    "help", "neofetch", "calc", "hexdump", "matrix", "history", "tty",
-    "beep", "reboot", "shutdown", NULL
+    "lazybox", "nano", "ls", "cat", "touch", "mkdir", "pwd", "cd", "wc", "echo",
+    "head", "tail", "stat", "cp", "grep", "hexdump", "tts", "alsamixer",
+    "lsmod", "insmod", "rmmod", "md5sum", "sha256sum", "crc32", "rand",
+    "certcheck", "capsh", "ipcs", "ifconfig", "ping", "arp", "dhclient",
+    "nslookup", "hdparm", "lspci", "speaker", "mouse", "virtinfo",
+    "io_uring_test", "uname", "free", "uptime", "dmesg", "ps", "top",
+    "sleep", "reboot", "poweroff", "clear", "help", "neofetch", "calc",
+    "matrix", "history", "tty", "beep", "shutdown", NULL
 };
 
 static void history_add(const char* cmd) {
@@ -51,26 +55,34 @@ static void redraw_line(const char* prompt, const char* buffer, size_t len, size
 static void cmd_help(void) {
     printk(ANSI_BRIGHT_CYAN "================== SUB-OS Production Command Reference ==================\n" ANSI_RESET);
     printk(ANSI_YELLOW "  [File & Storage Tools]\n" ANSI_RESET);
+    printk("    " ANSI_GREEN "nano [file]" ANSI_RESET "        - Full-screen visual interactive text editor\n");
     printk("    " ANSI_GREEN "ls [path]" ANSI_RESET "          - Directory list with type & inode numbers\n");
     printk("    " ANSI_GREEN "cat <file>" ANSI_RESET "         - Display file contents (supports /proc & /dev)\n");
-    printk("    " ANSI_GREEN "touch / mkdir" ANSI_RESET "      - Create files and directories in VFS\n");
+    printk("    " ANSI_GREEN "touch <file>" ANSI_RESET "       - Create empty files in VFS\n");
+    printk("    " ANSI_GREEN "mkdir <dir>" ANSI_RESET "        - Create directories in VFS\n");
+    printk("    " ANSI_GREEN "cd [dir] / pwd" ANSI_RESET "     - Change / Print current working directory\n");
     printk("    " ANSI_GREEN "hdparm" ANSI_RESET "             - Inspect ATA hard disk parameters & sectors\n\n");
+    printk(ANSI_YELLOW "  [Sound & Audio]\n" ANSI_RESET);
+    printk("    " ANSI_GREEN "tts <text>" ANSI_RESET "         - Phonetic formant voice synthesizer\n");
+    printk("    " ANSI_GREEN "alsamixer" ANSI_RESET "          - Sound architecture & audio card status\n\n");
+    printk(ANSI_YELLOW "  [Kernel & Modules]\n" ANSI_RESET);
+    printk("    " ANSI_GREEN "lsmod / insmod / rmmod" ANSI_RESET " - Manage dynamically loadable kernel modules\n\n");
     printk(ANSI_YELLOW "  [Cryptography & Security]\n" ANSI_RESET);
     printk("    " ANSI_GREEN "sha256sum <file>" ANSI_RESET "   - FIPS 180-4 SHA-256 secure hash\n");
     printk("    " ANSI_GREEN "md5sum <file>" ANSI_RESET "      - RFC 1321 MD5 message digest\n");
-    printk("    " ANSI_GREEN "crc32 <text>" ANSI_RESET "       - IEEE 802.3 32-bit CRC calculation\n\n");
+    printk("    " ANSI_GREEN "crc32 <text>" ANSI_RESET "       - IEEE 802.3 32-bit CRC calculation\n");
+    printk("    " ANSI_GREEN "certcheck / capsh" ANSI_RESET "  - X.509 keyring & POSIX capabilities\n\n");
     printk(ANSI_YELLOW "  [Networking Suite]\n" ANSI_RESET);
     printk("    " ANSI_GREEN "ifconfig" ANSI_RESET "           - Ethernet eth0 configuration & RX/TX metrics\n");
     printk("    " ANSI_GREEN "ping <ip>" ANSI_RESET "          - Send ICMP echo requests with latency ms\n");
-    printk("    " ANSI_GREEN "arp" ANSI_RESET "                - Display kernel ARP resolution cache table\n\n");
+    printk("    " ANSI_GREEN "dhclient" ANSI_RESET "           - Request IP lease from DHCP server\n");
+    printk("    " ANSI_GREEN "nslookup <host>" ANSI_RESET "    - Query DNS domain name server\n\n");
     printk(ANSI_YELLOW "  [System & Diagnostics]\n" ANSI_RESET);
     printk("    " ANSI_GREEN "neofetch" ANSI_RESET "           - System information & OS ASCII badge\n");
     printk("    " ANSI_GREEN "free / uptime" ANSI_RESET "      - Memory metrics and CPU uptime\n");
-    printk("    " ANSI_GREEN "dmesg" ANSI_RESET "              - Kernel boot ring buffer log\n");
-    printk("    " ANSI_GREEN "hexdump [addr] [n]" ANSI_RESET " - Memory hex inspector\n");
+    printk("    " ANSI_GREEN "dmesg / ps / top" ANSI_RESET "   - Kernel boot log & process manager\n");
     printk("    " ANSI_GREEN "calc [A] [op] [B]" ANSI_RESET " - Arithmetic calculator (+, -, *, /, %%)\n");
     printk("    " ANSI_GREEN "matrix" ANSI_RESET "             - Digital rain screen animation\n");
-    printk("    " ANSI_GREEN "tty [1-4]" ANSI_RESET "           - Switch virtual console (or Alt+F1-F4)\n");
     printk("    " ANSI_GREEN "reboot / shutdown" ANSI_RESET "   - Power management\n");
     printk(ANSI_BRIGHT_BLACK "Tip: Use TAB for autocomplete, Up/Down for command history.\n" ANSI_RESET);
 }
@@ -240,7 +252,7 @@ static void shell_process(const char* cmd) {
     }
     if (argc == 0) return;
 
-    // 1. LazyBox Applets
+    // 1. LazyBox Applets (ls, cat, touch, mkdir, cd, pwd, nano, etc.)
     if (lazybox_has_applet(argv[0])) {
         lazybox_run_applet(argv[0], argc, argv);
         return;
@@ -274,8 +286,10 @@ static void shell_process(const char* cmd) {
         printk(ANSI_YELLOW "Rebooting...\n" ANSI_RESET);
         pit_sleep(200);
         outb(0x64, 0xFE);
-    } else if (strcmp(argv[0], "shutdown") == 0) {
+    } else if (strcmp(argv[0], "shutdown") == 0 || strcmp(argv[0], "poweroff") == 0) {
         printk(ANSI_YELLOW "System halted.\n" ANSI_RESET);
+        outw(0x604, 0x2000);
+        outw(0xB004, 0x2000);
         while (1) hlt();
     } else {
         printk(ANSI_RED "Unknown command: %s. Type 'help' or 'lazybox'.\n" ANSI_RESET, argv[0]);
@@ -287,14 +301,16 @@ void shell_run(void) {
     size_t cmd_len = 0;
     size_t cursor_pos = 0;
     int history_idx = -1;
-
-    const char* prompt = ANSI_BRIGHT_GREEN "sub-os> " ANSI_RESET;
+    char prompt[128];
 
     printk(ANSI_BRIGHT_CYAN "\nWelcome to SUB-OS Modular Monolithic Linux Core!\n" ANSI_RESET);
     printk("Type '" ANSI_YELLOW "help" ANSI_RESET "', '" ANSI_YELLOW "lazybox" ANSI_RESET "', or '" ANSI_YELLOW "neofetch" ANSI_RESET "' to begin.\n\n");
 
     while (true) {
+        const char* cwd = vfs_getcwd();
+        snprintf(prompt, sizeof(prompt), ANSI_BRIGHT_GREEN "sub-os:" ANSI_BRIGHT_CYAN "%s" ANSI_BRIGHT_GREEN "> " ANSI_RESET, cwd);
         printk("%s", prompt);
+
         cmd_len = 0;
         cursor_pos = 0;
         cmd_buffer[0] = '\0';
@@ -361,12 +377,12 @@ void shell_run(void) {
 
             char c = (char)(key & 0xFF);
 
-            if (c == 0x03) {
+            if (c == 0x03) { // Ctrl+C
                 printk("^C\n%s", prompt);
                 cmd_len = 0; cursor_pos = 0; cmd_buffer[0] = '\0';
                 continue;
             }
-            if (c == 0x0C) {
+            if (c == 0x0C) { // Ctrl+L
                 tty_clear();
                 printk("%s%s", prompt, cmd_buffer);
                 continue;