cache-command

Run a command and cache its results.

Tested on Linux and macOS.

./cache-command [OPTIONS] -- COMMAND saves the stdout, stderr, and exit code of COMMAND in a cache and
returns the same on subsequent invocations.

$ echo -e '#!/bin/bash\n echo stdout; sleep 5; echo stderr >&2; exit 1' > five-seconds
$ chmod 755 five-seconds
$ TIMEFORMAT=%R
$ time ./five-seconds ; echo "Exit code: $?"
stdout
stderr
5.004
Exit code: 1
$ time ./cache-command -- ./five-seconds ; echo "Exit code: $?"
stdout
stderr
5.012
Exit code: 1
$ time ./cache-command -- ./five-seconds ; echo "Exit code: $?"
stdout
stderr
0.010
Exit code: 1

Note that cache-command should not be used to run programs that output sensitive information.

Inspired by this StackOverflow answer.

Requirements

• bash (tested with v4.4.19)
• GNU Coreutils:
  • tee)
  • sha256sum

Installation

make install

Usage

$ ./cache-command -h
Usage: cache-command [-b PATH] [-e SECONDS] [-h] [-p] [-r] [-v] -- COMMAND