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I can figure out why the following process substitution doesn't work:

kompare <( echo one two ) <( echo three four )

Kompare opens, but says that the input files are identical.

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up vote 2 down vote accepted

kompare probably needs a real file in order to read it more than once, but is not programmed to check whether the supplied arguments behave.

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Does that technically mean it's a bug in kompare? – Andrew Wood Mar 19 '13 at 15:59
@AndrewWood: It depends on what its documentation states. seems to only mention "compare two text files", so it is rather a feature request. – choroba Mar 19 '13 at 16:20
It may be impossible (or at least less efficient) to produce the smallest possible diff if you restrict the program to making a single, unidirectional pass through each file. zsh, at least, provides the =( cmd ) construct for process substitution when a real file is necessary. – chepner Mar 19 '13 at 22:31

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