Is there an equivalent to 'cut -c' in Windows cmd.exe?

Question

I have some files of fixed line size, fixed field size that I need to extract information from. Nornmally, I'd use Cygwin (cut et al), but that's not an option in this case due to (boneheaded) management policies I can't change. It has to be done using standard XP toolset included with Windows.

I need to extract the 10 characters at offset 7 and 4 characters at offset 22 (zero-based), and output them to a file but with a slight twist:

• The first field may have a negative, positive, or no sign (at the start or end). The sign should be moved to the front, or removed totally if it's positive.
• The second field should have leading and trailing spaces removed.

For example:

          1         2         3          <- ignore (these lines not in file,)
0123456789012345678901234567890123456789 <- ignore ( here only for info.)
xxxxxxx    15.22-yyyyyABCDzzzzzzzzzzz...
xxxxxxx   122.00+yyyyy XX zzzzzzzzzzz...
xxxxxxx         9yyyyyYYY zzzzzzzzzzz...

should produce (< indicates end of line):

-15.22,ABCD<
122.00,XX<
9,YYY<

Answer 1

This site has some pointers on how to extract substrings in cmd.exe: http://www.dostips.com/DtTipsStringManipulation.php

That site suggests that you can use

%varname:~2,3%

to subscript a variable. This seems to fill your needs, except you now have to get each line into a variable.

Next you want to look at the ghastly for loop syntax and if and branching (you can goto :labels in batch).

This stuff is all rather ugly, but if you really have to go there...

Here is a page in SO on looping through files and doing stuff to them: How do you loop through each line in a text file using a windows batch file?

Answer 2

If you working with modern windows, you are not restricted to cmd.exe commands natively, you can use vbscript. If your policy is not to use vbscript either, then I guess you should sack your management :)

Set objFS=CreateObject("Scripting.FileSystemObject")
strFile = "c:\test\file"
Set objFile = objFS.OpenTextFile(strFile)
strFirstLine = objFile.ReadLine
Do Until objFile.AtEndOfStream
    strLine= objFile.ReadLine
    var1 = Mid(strLine,10) ' do substring from position 10 onwards
    ' var2 = Mid (strLine,<pos>,<length>) ' get next offset and save to var2
    WScript.Echo var1 & var2  ' print them out.
Loop

Basically, to "cut" characters of a string, you use Mid() function. please look at the vbscript documentation to find out more.

Save the above as test.vbs and, on the command line, do

c:\test> cscript /nologo test.vbs > newfile

Of course, "substring" can also be done with pure cmd.exe but I will leave it to some others to guide you.

Update by Pax: Based on this answer, I came up with the following which will be a good start:

option explicit
dim objFs, objFile, strLine, value1, value2

if wscript.arguments.count < 1 then
    wscript.echo "Usage: process <input-file>"
    wscript.quit
end if

set objFs=createObject("Scripting.FileSystemObject")
set objFile = objFs.openTextFile(wscript.arguments.item(0))
do  until objFile.atEndOfStream
    strLine= objFile.readLine
    value1 = trim(mid(strLine, 8, 10))
    value2 = trim(mid(strLine, 23, 4))
    if right(value1,1) = "-" then value1 = "-" & left(value1,len(value1)-1)
    if right(value1,1) = "+" then value1 = left(value1,len(value1)-1)
    if left(value1,1) = "+" then value1 = mid(value1,2)
    wscript.echo value1 & "," & value2
loop

This matches all the requirements we had. We can make the offsets and lengths into command-line arguments later.

End update.

Answer 3

Here's a small script (needs to be in a BAT/CMD file) expanding on what Daren Thomas suggested:

@echo off
setlocal
set key=HKCU\Software\Microsoft\Windows\CurrentVersion\Ext\Stats\{D27CDB6E-AE6D-11CF-96B8-444553540000}\iexplore\AllowedDomains

echo.
echo Liste der fuer Flash im IE zugelassenen Domaenen:
echo =================================================
for /f "usebackq tokens=11 delims=\" %%l in (`call reg query "%key%" /s`) do echo. %%l
echo.
endlocal

The FOR loop is the central part. Note the use of command modifiers in double quotes. I specify tokens=11 because I'm only interested in the subkeys of AllowedDomains, which is at position 10.

Be sure to read the help in for /?. Daren is right when he says this stuff is all rather ugly. And it easily breaks down on modification. There's a lot of non-intuitive subtleties with cmd.exe script syntax.

By the way, the GUID is the COM class ID for the Shockwave Flash Add-on. It's been around since at least 2001 so might well continue to be relevant for the foreseeable future. The purpose of the script is to list the domains where Flash, which I prefer to block by default, has been allowed.