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Grep for a negative number

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# 1  
Old 01-02-2009
Grep for a negative number


I want to search for a return code of -3. Using grep "-3" *.* is giving a syntax error. Please suggest as to how can we search for this pattern using grep.

# 2  
Old 01-02-2009
grep thinks the '-' starts an option and tries to interpret it. Try escaping it, eg. grep '\-3' *.*
# 3  
Old 01-02-2009
Try -- to sign end of options. This is a general rule for such problems, e.g.
To grep -3 try:

grep -- -3 ...

If yoy want to remove a file named -panos you give:

rm -- -panos


This fact is true due to getopt function. This function is used by system programers
who write tools like grep, rm etc. The function marks end of option with a double dash
(--), so the behavior is similar for all tools using getopt to process options.

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