Directory Operations

Creating Directories Safely

mkdir -p creates any missing parent directories in one call and does not fail if the target already exists, making it the safe default for scripts.

Example: Creating Directories Safely

#!/bin/bash
mkdir -p project/src/utils
if [[ -d project/src/utils ]]; then
    echo "nested directories created"
fi
rm -rf project

Changing Directories Safely

cd can fail if the target does not exist or is not accessible. Chaining it with || exit 1 (or || return 1 inside a function) stops the script from continuing to operate in the wrong place.

Example: Changing Directories Safely

#!/bin/bash
mkdir -p work_area
cd work_area || exit 1
echo "Now in: $(pwd | xargs basename)"
cd ..
rmdir work_area

Using pushd and popd

pushd dir changes directory while remembering where you came from on a stack, and popd returns to that remembered location. This is convenient for scripts that need to temporarily work elsewhere and come back.

Note: Redirect pushd/popd output to /dev/null in scripts since their default directory-stack printout is rarely useful there.

Example: Using pushd and popd

#!/bin/bash
mkdir -p temp_place
pushd temp_place > /dev/null
echo "working here: $(pwd | xargs basename)"
popd > /dev/null
echo "back to: $(pwd | xargs basename)"
rmdir temp_place

Listing Directory Contents in a Script

While ls is fine for a human to glance at, scripts should generally prefer glob patterns or find to enumerate files, since ls output can be ambiguous with unusual filenames. Plain ls is still fine just to display a listing to a user.

Warning: Never parse ls output in scripts (e.g. for f in $(ls)); use globs (for f in *) or find instead.

Example: Listing Directory Contents in a Script

#!/bin/bash
mkdir -p listing_demo
touch listing_demo/a.txt listing_demo/b.txt
ls listing_demo
rm -rf listing_demo