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I saw in my programs properties they have a "%u" in the end of the command, what does this do? Using Ubuntu 10.04.

e.g. My Chrome have the command: /opt/google/chrome/google-chrome %U for what this %u is used here?

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up vote 3 down vote accepted

When you associate a file with a command, you can call this command with several arguments. %u simply means that the file name should go there. It is useful so you can put arguments after the filename. There are several other flags you can use.

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%u is the GNOME's file URI (such as file:///etc/motd or sftp://foohost/home/tom/file.txt). %s would get you the "normal" file path. – grawity May 6 '10 at 21:25
Thanks for the clarification. – petersohn May 7 '10 at 6:58

%u is used in Java's FileHandler to generate a unique field value.


A pattern consists of a string that includes the following special components that will be replaced at runtime:

* "/" the local pathname separator
* "%t" the system temporary directory
* "%h" the value of the "user.home" system property
* "%g" the generation number to distinguish rotated logs
* "%u" a unique number to resolve conflicts
* "%%" translates to a single percent sign "%"

Does that make sense in your particular context?

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Its not just in java programs that the %u appears – Tom Brito May 7 '10 at 14:34

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