Question

I need to know if xclip (the command is installed) because if it is available I want to send a command to it via the system() function, otherwise I want to display a message. Is there a way to know if the command exists?

Thanks

I mean programably

Answer 1

For something like xclip, you can just do:

if (system("xclip")==-1) // Check for command execution failed
  ...

and check the return value. A -1 indicates that xclip was not found. Or, you can execute something like:

if (system("which xclip")==0) // Check if command can be found
  ...

and check for a 0 return, indicating no failed arguments.