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Shell Programming and Scripting

Read and write in the file

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# 1  
Old 12-11-2012
Read and write in the file
Hello Guys, How all are doing?
I have an issue in Unix and want help from all of you
I have a file in UNIX which it read by line by line , If at the end of line '0' is written the it should fetch that line into another file and change '0' to '1'
and If at the end of line '1' is written then it should do nothing.

Temp file cannot be used
# 2  
Old 12-11-2012
Input and output samples please.
Quote:
Temp file cannot be used
Why? Homework?
# 3  
Old 12-11-2012
NO, Its not the homework, We never use the temp files in our Coding Standard. AND Rule is Rule..
# 4  
Old 12-11-2012
Is this what you want..?

Code:
$ cat file
rel/prod/amp.cfg1
rel/fld/amp.cfg0
rel/fld/amp.cfg/sdd1
rel/fld/amp.cfg/doc/cam/amp.cfg0

$ awk '{if(substr($0,length($0),1) == 0){print > "new_file";sub("0$","1")}}1' file
rel/prod/amp.cfg1
rel/fld/amp.cfg1
rel/fld/amp.cfg/sdd1
rel/fld/amp.cfg/doc/cam/amp.cfg1

$ cat new_file
rel/fld/amp.cfg0
rel/fld/amp.cfg/doc/cam/amp.cfg0

To change original file with sed..

try

Code:
sed -i 's/0$/1/' file

Last edited by pamu; 12-11-2012 at 10:27 AM..
# 5  
Old 12-11-2012
Quote:
Originally Posted by pamu
Is this what you want..?
...
To change original file with sed..

try

Code:
sed -i 's/0$/1/' file

The sed solution that ignores lines ending with 1 would look like this:
Code:
sed -e '/1$/d;s/0$/1/' /path/to/input >/path/to/output

PS: sed -i creates a tempfile somewhere...
# 6  
Old 12-11-2012
Quote:
Originally Posted by cero
The sed solution that ignores lines ending with 1 would look like this:
Code:
sed -e '/1$/d;s/0$/1/' /path/to/input >/path/to/output

PS: sed -i creates a tempfile somewhere...
As per OP's condition you should use..Smilie

Code:
sed -i '/1$/d;s/0$/1/' file

Quote:
Originally Posted by cero
PS: sed -i creates a tempfile somewhere...
But that file is not part of the code..Smilie
# 7  
Old 12-11-2012
No, It should change the old file form '0' to '1' and fetch the record into another file which has '0' marked in the master file
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