Inserting filename at the top of file

Shell Programming and Scripting
1

Hi Forum members,

I want to insert the filename at the top of file (i.e, first row only)

My file name is like

 asdf_432

And I want to insert this filename in first row as

filename is asdf with serial no. 432

Thanks in advance. :slight_smile:

2 
#! /bin/bash

f="asdf_432"
x=${f%_*}
y=${f#*_}

sed -i.bak "1i filename is $x serial no. $y" $f
1 Like
3

Try also:

$ echo filename is ${f%_*} serial no. ${f#*_} | cat - $f
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4

Code given above are working well, but what if the filename consists of more than 1 underscore. And I want to apply this condition on last underscore. i.e, my filename is like:

asdf_01_1234

And I need to print :

Filename is asdf_01 with serial no. 1234

at the top of the file.

Thanks in advance.

5

Hey, come on, be reasonable, and be creative. If you want to print "with", embed "with" into the text.
And, for "last underscore", man bash:

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