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Inserting argument into top of a file

 
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# 1  
Old 10-05-2006
Question Inserting argument into top of a file
Hi,

I am new to Unix, and I am trying to append a line of argument into a current file. I need this line to be inserted into the very top of the file. Does anyone know how this is done?

For example, I am trying: echo "insert to top" >> filename. This inserts the line at the bottom of the file. How do I get it to insert to the top??

Please help!
# 2  
Old 10-05-2006
Code:
{
  echo "This is the first line."
  cat originalFile
} > newFile
mv newFile originalFile

# 3  
Old 10-05-2006
Hi Glenn,

Thank you for your input. I cannot do the way you are showing me. My task is to input a line to an existing file without creating new or temporary file.

That is why I have used the >> symbol, but this inserts the line at the bottom. Do you know how to insert to the top without creating extra files?
# 4  
Old 10-05-2006
Code:
/bin/echo '1i\nNew Line Goes Here\n.\nwq' | ex -s myFile

# 5  
Old 10-05-2006
Whenever I see "without creating new or temporary file", I think "homework". You can use perl to edit files in place. Search the forums -- you will find many examples of this.
# 6  
Old 10-05-2006
Thanks for the input vgersh99. But again, that line of code inserts the line at the end of the file.. I am trying to get the line to be inserted at the top.

And Glenn, I understand where you are coming from, but I just don't wont to have so many temporary files created for no reason.

Any ideas??
# 7  
Old 10-05-2006
Code:
printf '1i\nNew Line Goes Here\n.\nwq!\n' | ex myFile

OR [in-line]

Code:
ex myFile <<EOF
1i
New Line Goes Here
.
wq
EOF

either one of the above inserts a line as the TOP line in a file.
Last edited by vgersh99; 10-05-2006 at 02:29 PM..
 
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