Print the working directory in a compact form (originally created for tmux status bar customization)

pwdshort.sh

#!/bin/sh

# Print a compact version of the current working directory.
# The home directory is replaced with ~, and long paths are truncated to the final part with < as a marker.
# Examples:
# /home/example/Documents becomes ~/Documents
# /example/of/a/really/really/long/path becomes <ly/really/long/path
# The maximum length can be set using the LIMIT variable.

LIMIT=20

HOME_REGEX=$(echo "$HOME" | sed 's/\//\\\//g')
TRANSLATED_PWD=$(echo "$PWD" | sed "s/^$HOME_REGEX/~/")
PWD_LENGTH=$(printf "%s" "$TRANSLATED_PWD" | wc -m)

if [ $PWD_LENGTH -le $LIMIT ]; then
	echo "$TRANSLATED_PWD"
else
	CUT_LIMIT=$(($LIMIT - 1))
	echo "<$(echo "$TRANSLATED_PWD" | cut -c $(($PWD_LENGTH - $CUT_LIMIT + 1))-)"
fi

Consider using #{=/-20/<:session_path} in tmux configuration instead. It accomplishes nearly the same thing as this script, with some minor differences:

• The home directory is not shortened to ~
• If the path is longer than the limit, the < is prepended without shortening the end part by 1, so the final result may be 1 longer than the limit