fallbacks in pipes

On frustrating thing with busybox ps is that it fails when you add the usual `-ax' formatters to it. This might happen with other situations too.

The sh `{ ...; }` syntax permit you to have fallbacks:


If `ps -ax' fails, ps is executed, and the output of either is piped into less.
Although different commands may behave differently so be cautious with this.

You may also want to check if a command exist before:


$browser will take the value of each one in the list and `command -v' will check if it exist and break the loop if so. At the end $browser will hopefully be an existing browser command.

P.S.: If you use ps in scripts, you might want to consider pgrep(1) and pkill(1), also in busybox to look for a process, rather than `ps + grep "ugly stuff"'.