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Globbing or not globbing

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# 1  
Old 10-01-2012
Question Globbing or not globbing
Hi guys,

Here is a simple script. It writes the current time to specific files in a directory.
The arguments are the names of the files to write the date to (without path nor extension).
Code:
root:~# cat /usr/local/bin/dummy.sh
#!/bin/sh -e
for file in $@; do
    date >> /var/lib/$file.dat
done

The command
Code:
root:~# dummy.sh a1 a2 a3

will write the current time to
Code:
/var/lib/a1.dat
/var/lib/a2.dat
/var/lib/a3.dat

I'd like to allow wildcards in the arguments.
But the command
Code:
root:~# dummy.sh a*

will try to write the current time to files in /var/lib/ named after files in /root/a* plus the extension .dat.

To achieve my goal, I'd need globbing to be disabled in
Code:
for file in $@

but enabled in
Code:
date >> /var/lib/$file.dat

How's that doable?

Best regards
Santiago
# 2  
Old 10-01-2012
If you assume that /var/lib/a*.dat will expand to something like /var/lib/ab.dat /var/lib/ac.dat, your command line will become date >> /var/lib/ab.dat /var/lib/ac.dat and will fail. Only the first word after >> will be considered as the file-name to be appended to and the rest of the file-names will be considered as arguments to date.
Last edited by elixir_sinari; 10-01-2012 at 10:16 AM..
# 3  
Old 10-01-2012
You will need to call the script like so
Code:
dummy.sh a\*.dat

because the glob expansion happens in the shell, not the script Smilie
# 4  
Old 10-01-2012
You can try something like this dummy.sh 'a*'

--ahamed
# 5  
Old 10-01-2012
That's right elixir_sinari.
Please forgive my mistake and considere the following code :
Code:
root:~# cat /usr/local/bin/dummy.sh
#!/bin/sh -e
for arg in $@; do                       # disable globbing
    for file in /var/lib/$arg.dat; do   # enable globbing
        date >> $file
    done
done

Sorry Skrynesaver and ahamed101. Escaping the wildcard doesn't change anything.
Last edited by chebarbudo; 10-01-2012 at 10:27 AM..
# 6  
Old 10-01-2012
Code:
#!/bin/sh -e
cd /var/lib
for arg in $@; do
    for file in /var/lib/$arg.dat; do  
        date >> $file
    done
done

then call it this way:
sh -f -c "./dummy.sh a*"
--
Bye
Last edited by Lem; 10-01-2012 at 10:34 AM..
This User Gave Thanks to Lem For This Post:
elixir_sinari
# 7  
Old 10-01-2012
Hey Lem,
Thanks for your help.
That still leaves me with one problem.
If run several times, I'll end up with files named a1.dat.dat.dat.dat.
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