dotlockfile

mailbox-style file locking utility

TLDR

Create a lockfile

$ dotlockfile [file.lock]

Create with retry

$ dotlockfile -r [5] [file.lock]

Remove a lockfile

$ dotlockfile -u [file.lock]

Lock with PID checking

$ dotlockfile -p [file.lock]

Try lock once (no wait)

$ dotlockfile -r [0] [file.lock]

Lock with timeout in seconds

$ dotlockfile -r [10] -l [file.lock]

dotlockfile creates lockfiles using the mailbox locking convention (name.lock). It provides atomic file locking for scripts and applications that need to serialize access to resources.The tool handles retry logic, stale lock detection, and PID tracking. With -p, it writes the process ID to the lockfile enabling detection of dead lock holders.dotlockfile is commonly used in shell scripts to prevent concurrent access to files or ensure only one instance of a script runs at a time.

PARAMETERS

LOCKFILE

Path to lockfile to create/remove.

-r RETRIES

Number of retries (0 = try once, -1 = infinite).

-u, --unlock

Remove the lockfile.

-p, --use-pid

Write PID to lockfile.

-l

Lock (default action).

-c, --check

Check if lock is stale.

--help

Display help information.

INSTALL

sudo apt install liblockfile-bin

sudo dnf install liblockfile

sudo pacman -S liblockfile

sudo apk add liblockfile

brew install liblockfile

nix profile install nixpkgs#liblockfile

CAVEATS

Lockfiles on network filesystems may not be reliable. Must manually remove locks on script exit. Stale lock detection requires -p option. Not suitable for high-contention scenarios.

HISTORY

dotlockfile implements the traditional Unix lockfile convention, widely used for mailbox locking. It's part of the liblockfile package providing standardized file locking utilities.