Branch on whether a pattern exists.

Linux Commands: Use grep -q in a conditional so an ordinary no-match result is not an unhandled failure.

if grep -qF -- 'enabled=yes' settings.txt; then
  printf 'Enabled\n'
else
  printf 'Disabled\n'
fi

Expected output EXAMPLE

Enabled

Details

Run in Bash on GNU/Linux in a scratch directory. Tested with the GNU utilities supplied by Ubuntu. Use grep -q in a conditional so an ordinary no-match result is not an unhandled failure.

✓ Verified

Tested on Ubuntu 24.04.5 LTS · 2026-11-02 18:01:36 UTC · GNU bash, version 5.2.21(1)-release (x86_64-pc-linux-gnu) · bash 5.2.21-2ubuntu4; grep 3.11-4build1

Test inputs, results and environment

The exact published code ran in a dedicated Linux test container with prepared inputs. Unprivileged snippet process, external networking disabled, read-only root filesystem, and a fresh temporary working directory. Fixtures and output records are isolated from the application database. Testing covers this example and its stated checks, not every input, operating system, or runtime version. The Linux container shares its host's kernel; this is not a native Windows test.

Architecture / host kernel: x86_64 / 6.18.54.1-microsoft-standard-WSL2
Snippet identity / locale: uid=65534, gid=65534 (unprivileged) / C.UTF-8
Interpreter invocation: bash -euo pipefail -c <published code>
Container image ID: sha256:32dc2d998158b6554c99b73b533f423696a0f3e31e8cbea9db10b5eee9a2fadd
Code SHA-256: 22927edb356c786747c2855c0902d6edfb0f0b47fd6ab2b50edd7603ceeef345
Dependencies: bash 5.2.21-2ubuntu4; grep 3.11-4build1

Test input setup

These are the prepared inputs used by the test harness. See Details above for the prerequisites and how to run this example.

printf 'enabled=yes\n' > settings.txt

Observed standard output

Enabled

Exit code: 0. Standard error: empty. Validation: Exact stdout comparison. System-dependent values above are one recorded run.