tail - Command Generator

Print the last 10 lines of each FILE to standard output. With more than one FILE, precede each with a header giving the file name. With no FILE, or when FILE is -, read standard input.


Last/Start NUM bytes
output the last NUM bytes; or use -c +NUM to output starting with byte NUM of each file. NUM may have a multiplier suffix: b 512, kB 1000, K 1024, MB 1000*1000, M 1024*1024, GB 1000*1000*1000, G 1024*1024*1024, and so on for T, P, E, Z, Y. CMD: -c, --bytes
{name|descriptor}. output appended data as the file grows; an absent option argument means 'descriptor'. With --follow (-f), tail defaults to following the file descriptor, which means that even if a tail'ed file is renamed, tail will continue to track its end. This default behavior is not desirable when you really want to track the actual name of the file, not the file descriptor (e.g., log rotation). Use --follow=name in that case. That causes tail to track the named file in a way that accommodates renaming, removal and creation. CMD: -f, --follow
Last/start NUM lines
output the last NUM lines, instead of the last 10; or use -n +NUM to output starting with line NUM. CMD: -n, --lines
Max unchanged stats
--max-unchanged-stats=N. With --follow=name, reopen a FILE which has not changed size after N (default 5) iterations to see if it has been unlinked or renamed (this is the usual case of rotated log files); with inotify, this option is rarely useful. CMD: --max-unchanged-stats
with -f, terminate after process ID, PID dies. CMD: -p, --pid
Sleep interval
--sleep-interval = N. with -f, sleep for approximately N seconds (default 1.0) between iterations; with inotify and --pid=P, check process P at least once every N seconds. CMD: -s, --sleep-interval