Linux How to htop specific commands

Question

Linux Centos 6,64

I am using following command for displaying htop in the command column

htop -u command

How do I do for it to show only a specific command which i choose from those running commands list?

Thanks

Answer 1

In htop -u the parameter is a user name, not a command.

The only option to monitor a specific command is -p, but this takes a PID, so the command name must be converted to a PID first, which pidof will do.

If more than one instance of a command is running, pidof returns a space-separated list of PIDs, but the -p option takes a comma-separated list, so the pidof output must be converted:

htop -p $(pidof command | sed 's/ /,/g')

This is best incorporated into a function or script, in which case the command will be:

htop -p $(pidof "$1" | sed 's/ /,/g')

Although I first think of sed for batch editing, in this case the simpler tr command could be used:

htop -p $(pidof "$1" | tr ' ' ',')

Note that GUI system monitors, such as qps and ksysguard, can filter the output and show specific commands directly (though the text-based filter may also pick up the command name if it happens to appear in the parameter list of another command).