cd - Change Directory

Change the current working directory.

Source: src/execution/builtins.f90:builtin_cd

Synopsis

cd [directory]
cd -
cd ~
cd ~username

Description

Changes the shell's current working directory. If no argument is given, changes to the home directory ($HOME).

Options

cd has no flags. The argument is interpreted as a directory path.

Arguments

Behavior

Path Resolution

1. If the path contains /, it's used directly
2. If the path doesn't contain /, CDPATH is consulted
3. CDPATH is a colon-separated list of directories to search
4. Falls back to current directory if not in CDPATH

Environment Updates

On successful directory change:

• OLDPWD is set to the previous directory
• PWD is set to the new directory
• Terminal title is updated (if interactive and color-capable)
• Directory is added to directory history (for prevd/nextd)

Implementation Details

From builtins.f90:

! cd with no argument goes to HOME
if (num_args == 0) then
    target_dir = get_environment_var("HOME")

! cd - goes to OLDPWD
else if (trim(args(1)) == "-") then
    target_dir = shell%oldpwd
    print_dir = .true.

Return Value

Examples

# Go home
cd

# Go to /tmp
cd /tmp

# Go back to previous directory
cd -

# Use CDPATH
export CDPATH="$HOME/projects"
cd myproject  # finds ~/projects/myproject

Environment Variables

Related Commands

• pushd - Push directory onto stack
• popd - Pop directory from stack
• dirs - Display directory stack
• prevd - Go to previous directory in history
• nextd - Go to next directory in history

Notes

• Symlinks are preserved (logical path behavior)
• The directory history maintained by fortsh is separate from the directory stack (pushd/popd)
• cd without arguments always goes to $HOME, even if $HOME is unset (falls back to /)