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Read a number from file and place it back

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# 1  
Old 06-09-2009
Read a number from file and place it back

Hi All,

I want to read one number from the file.
Only one number will be there in the file.
then i have to increment the number in my script and put it back in the same file.

Is it possible?
Can anybody help me?

# 2  
Old 06-09-2009
Something like this?

awk '$0++' file > newfile && mv newfile file

# 3  
Old 06-09-2009
Hi Franklin,

I want to place the incremented value in the same old file.

say my file name is "file.txt" which has number 5 in it.

once i run the script, this value should be taken and 6 should be placed in the file "file.txt".

I think you got my requirement.


-----Post Update-----

Hi Franklin,

It is working fine.
Thanks a lot...Smilie

# 4  
Old 06-09-2009

Try this code:

read i < a
i=`expr $i + 1`
echo $i > a
cat a

It is working perfectly fine in bash.

Here "a" is a file name where the number is stored & "i" is a temp variable.

Let me know if you need any more info.
# 5  
Old 06-09-2009
Hi Dcoolsam,

Thanks a lot ,,,,
Your code suits my requirement.
But one change is needed, here it is printing the number also in echo line...
i dont want to print that,,,
how can i fix it...

# 6  
Old 06-09-2009
Hey Vinay,
Your task is getting accomplished by just first 3 lines of my code.
Last line is just to print that value.
You can remove that last line : cat a

You check the incremented value in the file.
It will be incremented.

# 7  
Old 06-10-2009
Hi Dcoolsam,

Yes i checked. It is working properly.
Thanks a lot,,,,Smilie


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