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Batches multiple invocations of ksdiff to open in a single Kaleidoscope window if they happen within a few seconds of eachother. This is useful for Kaleidoscope integration with P4V, since it makes a multi-file diff open in a single window. If it doesn't quite pick up all your files, try setting TIMEOUT to more than 4 seconds.
# Commandline tools required for this script:
# pidof (can be installed with `brew install pidof`)
# lockfile (can be installed with `brew install procmail`)
# Number of seconds we wait after a file is received before we consider the
# batch to be completed.
# Title of the tab in Kaleidoscope
LABEL="P4V ksdiff-batch"
# FIFO we communicate with the "batch master" for.
# PID of the batch master, to see if it's still running.
# This function forks a process that just reads the FIFO for a new pair of files
# to read. If $TIMEOUT seconds pass without a new pair of files, it closes the
# Kaleidoscope "changeset" and deletes the FIFO and pidfile.
function fork_batchmaster()
rm -f "$fifo" "$pidfile"
mkfifo "$fifo"
( session="batch-$$"
exec 3<> "$fifo"
function cleanup() {
if [ ! -z "$(pidof Kaleidoscope)" ]; then
ksdiff --mark-changeset-as-closed "$session"
exec 3>&-
rm -f "$fifo" "$pidfile"
trap "cleanup" "EXIT"
while read -r -t $TIMEOUT -u 3 line1; do
if read -r -t $TIMEOUT -u 3 line2; then
ksdiff --partial-changeset --label "$LABEL" --UUID "$session" "$line1" "$line2"
done ) &
echo "$?" > "$pidfile"
export PATH=$PATH:/usr/local/bin
# We use a lockfile to prevent interleaving of lines in the FIFO, and to ensure
# that two different processes aren't trying to become the batchmaster at the
# same time.
function delete_lock() { rm -f "$lock"; }
# Retry interval is 1 second so that the batchmaster won't time out waiting for
# new files while we're waiting for the lock.
if ! lockfile -1 -l 10 "$lock"; then exit 1; fi
# Ensure we delete the lock at exit, no matter what.
trap "delete_lock" "EXIT"
# If there's no pidfile, or the pid is dead, we assume the responsibility of
# creating a new batchmaster.
if [ ! -f "$pidfile" ] || ! kill -0 $(cat "$pidfile") >/dev/null 2>&1; then
# Assuming everything went OK, there should be a FIFO available, and we can
# write to it.
if [ -p "$fifo" ]; then
echo "$1" > "$fifo"
echo "$2" > "$fifo"
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