Trying to follow GNU Parallel as job queue with named pipes with GNU parallel 20201222, I run into issues of parallel not executing the last commands piped into it via tail -n+0 -f.
To demonstrate, I have 3 terminals open:
# terminal 1
true > jobqueue
tail -n+0 -f jobqueue | parallel
# terminal 2
tail -n+0 -f jobqueue | cat
Adding a single small test command to the queue:
# terminal 3
echo "echo test" >> jobqueue
Only terminal 2 prints "echo test", gnu parallel does not output anything.
# terminal 3
for i in `seq 10`; do echo "echo $i" >> jobqueue; done
Only terminal 2 prints "echo 1", ..., "echo 10" (one in each line), gnu parallel does not output anything.
# terminal 3
for i in `seq 100`; do echo "echo $i" >> jobqueue; done
Terminal 2 prints "echo 1", ..., "echo 100". Terminal 1 prints the lines "test", "1", ..., "10", "1", ..., "99", the last line "100" is missing.
Rerunning tail -n+0 -f jobqueue | parallel outputs all up to "99". Rerunning this with --resume --joblog log appended, outputs one more line ("100") but then also lags behind once new lines are added to joblog. For GNU parallel 20161222, the initial run only gets to line "84".
How can I force gnu parallel to flush its input queue on every line?
