bash append file from multiple thread
sem
from GNU Parallel should be able to do it:
sem --id mylock "head -n 256 thread_processed.txt >> output"
It will start a mutex named mylock.
If you are concerned that someone might read output
while the head
is running:
sem --id mylock "cp output o2; head -n 256 thread_processed.txt >> o2; mv o2 output"