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Find Special/Null/Control Chars and Print Line Numbers


 
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# 1  
Old 08-20-2013
Find Special/Null/Control Chars and Print Line Numbers

Hi All,

This might be a basic question... I need to write a script to find all/any Speacial/Null/Control Chars and Print Line Numbers from an input file.

Output something like

Null Characters in File Name at : Line Numbers
Line = Print the line
Control Characters in File Name at : Line Numbers
Line = Print the line

Please help.

-K
# 2  
Old 08-20-2013
Code:
grep -n "[[:cntrl:]]" file

# 3  
Old 08-20-2013
Hardest first: null is not handled by most tools. 'cat -v' can turn it into '^@' C/C++/PERL/JAVA/etc. can read byte by byte and translate anything. grep can print line numbers and lines containing [^ -~] (not between the space and tilde characters, the ASCII non-control characters).

Text does not normally have such, so the concept of lines and line numbers is funny. File names are in directories not flat files, generally, but a flat file could have a file name in it, if you can figure out how to frame it. Are you describing a process ot examine many files?

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