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Simple Sed

 
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# 1  
Old 02-14-2006
Simple Sed
Hello. Just trying to write this line to an empty file. CAT shows nothing was written. Any suggestions or answers?
Code:
#!/bin/bash -x
THIS=FIRSTLINE
sed '1w '$THIS'' testfile
cat testfile

Thank you.
# 2  
Old 02-14-2006
The quotes make a difference for sure.

But the w command in sed works as follows:
Code:
The read (r) and write (w) commands allow you to work directly with files. Both take a single argument, 
the name of a file. The syntax follows:

    [line-address]r file
    [address]w file

The read command reads the contents of file into the pattern space after the addressed line. 
It cannot operate on a range of lines. The write command writes the contents of the pattern
 space to the file.

Read http://www.unix.org.ua/orelly/unix/sedawk/ch05_11.htm

sed needs an input file. In your case, it is testfile. Thats not where the writing is done.

Your qestion can be answered as

Code:
echo "$THIS" > output.file

# 3  
Old 02-14-2006
Thank you Vino. Also alot easier to do it this way.
 
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