How to change the output file name in a bat file? - windows

Question

I'm trying to change the output file name, fOut, in a bat file, but have no luck so far.
I'm developing on Windows 7 and will deploy the code to Windows 2003 server.
The code looks like this:
set fName=%1
set fExt=%fName:~-5,-1%
set fOut=%fName:~0,-5%_PAD%fName:~-5%
Examples of fOut:
abcdc2evv_PAD.dat
abcdefgh33ij_3737_PAD.dat
How can I change fOut to get the following file names?
A. Adding FMT_ at the beginning of the file name:
FMT_abcdc2evv_PAD.dat
FMT_abcdefgh33ij_3737_PAD.dat
B. Adding FMT_ at the beginning of the file name and remove _PAD before .dat:
FMT_abcdc2evv.dat
FMT_abcdefgh33ij_3737.dat
Addendum:
Just one argument is passed to the bat file: path + file name.
x.bat "C\test\xxx.dat"
In the bat file:
#echo ^-input file name = ^%1
set fName=%1
set fExt=%fName:~-5,-1%
set fOut==%fName:~0,-5%_PAD%fName:~-5%

Answer 1

I don't know if I'm missing something obvious - it's not clear what the input to this script is.
However adding FMT_ before should just be a case of changing:
set fOut=%fName:~0,-5%_PAD%fName:~-5%
to:
set fOut=FMT_%fName:~0,-5%_PAD%fName:~-5%
or if you want to put the FMT_ version into another variable, then:
set bob=FMT_%fOut%
As for removing _PAD, can you not just repeat the SET fOut line without the _PAD? This would seem to be the simplest way to do it. In fact, removing _PAD and prefixing FMT_ would seem to simply be this:
set bob=FMT_%1

Answer 2

if you want to remove pad just take it out of your assignment statement
you have:
set fOut=%fName:~0,-5%_PAD%fName:~-5%
you want:
set fOut=%fName:~0,-5%fName:~-5%
to add FMT_ just add it at the beginning of the file name:
set fOut=%FMT_%fName:~0,-5%_PAD%fName:~-5%

Answer 3

If you want to separate the filename from the extension, don't mess around counting chars; there is a built-in method (described in for /?):
echo Filename=%~n1
echo Extension=%~x1
echo resulting file="FMT_%~1"
REM without _PAD, following with _PAD
set filename="FMT_%~n1_PAD%~x1"
If there is really need to remove _PAD (as Chris already noted, you are explicitely adding it with your code), just replace _PAD. with . only:
set filename=%filename:_PAD.=.%