Print to stdout each new X11 selection value separated by a single newline

xpipe

#!/bin/bash

# Print to stdout each new X11 selection value.  By default operates
# on "xsel -b".  Any passed arguments are used instead of
# "-b" verbatim.


set -o errexit -o nounset -o pipefail

# Set argv to -b (operating on the CLIPBOARD selection) if
# not specified.
set -- "${@:--b}"


# Take control of the selection and wait until some other program
# takes it back, changing its value.
while xsel -i "$@" -n <<< '' > /dev/null; do
    # Print the new selection value.  $(…) is used to strip the
    # trailing newlines, printf is used for adding exactly one
    # newline afterwards.
    printf '%s\n' "$(xsel "$@" -o)"
done