there might be situations, where the command does not exist on PATH, like shell aliasing or internal command.
This is tricky. It is pretty system dependent on what the default shell for system is. If you know it is bash, you could shell out and do a type COMMANDNAME.

-- 
Ronald Fischer <ynnor@mm.st>

In reply to Re^2: How to find whether an external commands exists by rovf
in thread How to find whether an external commands exists by sathiya.sw

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