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How can I ... (Modifying large ASCII files)


 
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# 1  
Old 07-19-2001
Question How can I ... (Modifying large ASCII files)

Hi Everybody!

Situation:
I have a large ASCII file (for example: 1-2 Mbytes) without linebreaks (\n).

Task:
I like inserting linebreaks after all 420 digits (byte).
(pattern: *[420pcs]\n*[420pcs]\n*[420pcs]\n...etc.)

My problem:
How? :-)
I like using shell script or (maybe) AWK (short) program.

Please, help me.

Bye
hviktor
# 2  
Old 07-19-2001
I dont think you will find a way to do that with a shell script. The only command that I know of would be csplit in a CShell script. this command only allow as maximum of 100 characters to be read at a time. I would suggest you look at a small C program to read the file character by character using a for loop.
# 3  
Old 07-20-2001
Code:
cat $file|sed ' s/420pcs/420pcs\
/gw newfile'

try that
 

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