run command with opposite return code

not () { "$@" && return 1 || return 0; }
Useful in while and if statements if not grep string filename; then echo string not found; exit 1; fi

By: arcege
2009-09-23 01:09:53

What Others Think

why not write to if ! grep string filename ; then echo "string not found" exit 1 fi It is not a good idea to write a function, just use `!' , that's all
twfcc · 635 weeks and 3 days ago
what twfcc said. Obviously "not" is built into the language.
pixelbeat · 635 weeks and 3 days ago

What do you think?

Any thoughts on this command? Does it work on your machine? Can you do the same thing with only 14 characters?

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