Execute a command if a file exists

grep -sq "" /etc/lsb-release && lsb_release -rd
grep -sq "" filename && command grep can be used in combination with && to run a command if a file exists.

-3
By: int19h
2009-02-17 05:21:20

What Others Think

Sure this works, but its a misuse of grep, there is a standard way of doing this: if [[ -r /etc/lsb-release ]]; then lsb_release -rd; fi [[ -r /etc/lsb-release ]] && lsb_release -rd Either of those two will work. The first one is more flexible as you can do multiple commands within the if-statement without having to chain them with a bunch of '&&' The '-r' flag here tests to see if the file exists and is readable. If you just want to see if the file exists then you can use '-e'. There are other flags that test whether the file is writable, whether it is a block device etc etc. 'man 1 test' if you want to see the rest.
SiegeX · 504 weeks and 5 days ago

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