Using commandoutput as a file descriptor

diff rpm_output_from_other_computer <(rpm -qa|sort)
Description is moved to "Sample output" because the html sanitizer for commandlinefu breaks the examples..
Sample Output
# Standard diff output...

Using <(command_here) will do the same job as "command_here > command_output" and then use command_output instead of <(command_here).
This trick can be used for much more than diff as the command that get this as a parameter wont see the different between the <( ) file descriptor and a normal file.
Eg: diff /etc/passwd <(ssh remotehost "cat /etc/passwd")

ls <(ls), will give you a little hint why this works :)

0
By: xeor
2011-06-25 11:45:15

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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