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# 1  
Old 11-11-2009
Question about variables

What does this mean?

Code:
#!/bin/bash
BACKUPFILE=backup-$(date +%m-%d-%Y)
archive=${1:-$BACKUPFILE}


Last edited by pludi; 11-11-2009 at 04:37 PM.. Reason: code tags, please...
# 2  
Old 11-11-2009
The variable archive gets set to $1 if it exists otherwise if get set to "backup-$(date +%m-%d-%Y) (e.g. "backup.10-29-2009")
# 3  
Old 11-11-2009
i would suggest reading up on bash parameter substitution... It's comes in really handy if you have to do a lot of manipulation with a single variable otherwise you have to add on a bunch of test logic.
# 4  
Old 11-11-2009
Your question(s) could easily be answered by searching the Internet with Google. Google is your friend Smilie

Have a read of these links:

Shell expansion

Operations on variables

Regards
# 5  
Old 11-11-2009
thanksSmilie

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