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Trying to grep for '--' occurance

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# 1  
Old 06-16-2011
Trying to grep for '--' occurance
Hello

Im trying to grep for a string in grub.conf . I've used the -F option since its a long string, but when i execute, i run into errors. Script and output below.

GRUBPASSWD="password --md5 xyz"
if grep -Fxq $GRUBPASSWD /etc/grub.conf
then
.
.
output:
grep: unrecognized option `--md5'

Can anyone please help?

Thanks
# 2  
Old 06-16-2011
Try this line instead as the --md5 is being mistaken for a command line and the quotes may help too.

Code:
if grep -Fxq -- "$GRUBPASSWD" /etc/grub.conf

This User Gave Thanks to SteveDawe For This Post:
bludhemn
# 3  
Old 06-16-2011
How about '[-]-md5' ? The square brackets convince grep that it's not an option without altering the meaning of the expression. This trick's also useful for grepping for program names -- instead of ps | grep program | grep -v grep, just ps | grep '[p]rogram' and grep won't match its own existence.
# 4  
Old 06-16-2011
Quote:
Originally Posted by SteveDawe
Try this line instead as the --md5 is being mistaken for a command line and the quotes may help too.

Code:
if grep -Fxq -- "$GRUBPASSWD" /etc/grub.conf

This worked...thank you!!

Quote:
Originally Posted by Corona688
How about '[-]-md5' ? The square brackets convince grep that it's not an option without altering the meaning of the expression. This trick's also useful for grepping for program names -- instead of ps | grep program | grep -v grep, just ps | grep '[p]rogram' and grep won't match its own existence.

I tried this, enclosing the --md5 as you suggested.

This is the output
grep: '[-]-md5': No such file or directory
grep: xyy.: No such file or directory

Thanks
# 5  
Old 06-16-2011
My apologies, I misunderstood the problem: Your string was getting split on spaces. The quotes like SteveDave suggested fix it. (I don't think the -- before "$GRUBPASSWORD" is necessary but it certainly doesn't hurt, either.)
# 6  
Old 06-16-2011
Yes, they work with or without the "--" before the variable.

Thanks again
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