A Bash script that automatically sets the PERL5LIB environment variable when you cd into a directory containing a Perl project.
It scans for lib/ directories containing .pm files, applies intelligent exclusions and limits, and sets or appends to PERL5LIB accordingly.
- Recursively scans for
lib/directories under the current directory - Includes only those containing
.pmfiles - Excludes common build/IDE directories and versioned-release folders
- Skips scanning when inside specific top-level directories (like
~/git) - Optionally limits how many
lib/directories to include - Supports dry-run mode and verbose debugging
- All behaviour is configurable via environment variables
Save the script somewhere convenient, for example:
mkdir -p ~/bin
curl -o ~/bin/perl5lib_auto.sh https://raw.githubusercontent.com/davorg/perl5lib_auto/main/perl5lib_auto.sh
chmod +x ~/bin/perl5lib_auto.shThen source it in your ~/.bashrc or ~/.bash_profile:
source ~/bin/perl5lib_auto.shOpen a new terminal or run source ~/.bashrc to activate it.
You can customise the script’s behaviour with the following environment variables:
| Variable | Description |
|---|---|
PERL5LIB_LIB_CAP |
Max number of lib/ dirs to include (default: 3) |
PERL5LIB_FORCE |
Set to 1 to override exclusions and cap |
PERL5LIB_APPEND |
Set to 1 to append to existing PERL5LIB rather than overwrite |
PERL5LIB_VERBOSE |
Set to 1 for debug output |
PERL5LIB_DRYRUN |
Set to 1 to preview PERL5LIB without actually setting it |
PERL5LIB_EXCLUDE_DIRS |
Colon-separated absolute directory paths to skip entirely (default: ~/git) |
PERL5LIB_EXCLUDE_PATTERNS |
Colon-separated substrings to filter out of matched lib/ paths (default: .vscode:blib) |
PERL5LIB_VERBOSE=1 cd ~/projects/MyApp # Show matched lib dirs
PERL5LIB_DRYRUN=1 cd ~/projects/MyApp # Preview what would happen
PERL5LIB_FORCE=1 cd ~/git # Force scanning even if excluded
PERL5LIB_LIB_CAP=5 cd ~/src/BigProject # Temporarily increase capBy default, the script behaves as if the following were set:
export PERL5LIB_LIB_CAP=3
export PERL5LIB_EXCLUDE_DIRS="$HOME/git"
export PERL5LIB_EXCLUDE_PATTERNS=".vscode:blib"MIT or similar — feel free to adapt for your own shell environment.