what does export do?

[Matthew Miller]

On Fri, May 20, 2005 at 11:27:39AM +0100, Paul Howarth wrote:
> THUFIR HAWAT wrote:
> >but it doesn't say which files are effected by the command.  is it
> >stored somewhere?
> No files are affected by the command. All it does is mark a shell 
> variable as being an environment variable that is passed on to any 
> subsequent commands you execute *from that shell*.

Watch this:

$ echo $VARIABLE

$ VARIABLE=something
$ echo $VARIABLE
something
$ bash   # <-- starting another shell, which is just another program
$ echo $VARIABLE

$ exit   # back to the main shell
exit
$ echo $VARIABLE
something
$ export VARIABLE
$ bash   # <-- a new subshell again
$ echo $VARIABLE
something


-- 
Matthew Miller           mattdm at mattdm.org        <http://www.mattdm.org/>
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