Is it possible to pass unprocessed parameters in a CALL command? - windows

Question

Take for instance the following example files a.bat and b.bat:
a.bat
#echo off
echo in a: %*
call b %*
b.bat
#echo off
echo in b: %*
and consider this invocation and output:
c:\>a 1 2 3 %% %%%%
in a: 1 2 3 %% %%%%
in b: 1 2 3 % %%
Is there a way to pass the parameters from the command line to b.bat such that it sees the same parameters that a.bat saw? Is it possible to prevent the system from processing the parameters, i.e. removing the escaping % character?

Answer 1

Because this looks so simple, I assume that I must have missed something, but from what you've posted, this looks like all you should need:
C:\a.cmd
#Echo In %~n0: %*
#Call "b.cmd" %%*
C:\b.cmd
#Echo In %~n0: %*
Example:
C:\>a 1 2 3 %% %%%%
In a: 1 2 3 %% %%%%
In b: 1 2 3 %% %%%%

Answer 2

Yes you can do that, but instead of removing a character, you need to add more escape characters.
But to solve it for any (or at least most) parameter you need to escape all problematic characters &|<>"^
This can handle even parameters like:
a.bat Bob^&Alice say: "Cat & dog"
#echo off
REM *** Fetch all arguments
goto :init :initCallBack
:initCallBack
REM *** Prepare the arguments for a secure CALL
call :prepareArgument allArgs arg
REM *** b.bat will see the same arguments like this file
call b.bat %%allArgs%%
exit /b
:init
::: Get all arguments with minimal interference
::: Only linefeeds and carriage returns can't be fetched
::: Only linefeeds can create a syntax error
::: return arg=All arguments, arg1..arg<n>=A single argument
setlocal EnableDelayedExpansion
set "argCnt="
:getArgs
>"%temp%\getArg.txt" <"%temp%\getArg.txt" (
setlocal DisableExtensions
(set prompt=#)
echo on
if defined argCnt (
for %%a in (%%a) do rem . %1.
) ELSE (
for %%a in (%%a) do rem . %*.
)
echo off
endlocal
set /p "arg%argCnt%="
set /p "arg%argCnt%="
set "arg%argCnt%=!arg%argCnt%:~7,-2!"
if defined arg%argCnt% (
if defined argCnt (
shift /1
)
set /a argCnt+=1
goto :getArgs
) else set /a argCnt-=1
)
del "%temp%\getArg.txt"
goto :initCallBack
:prepareArgument
::: Convert a string, so it can be used as an argument for calling a program
set "var=!%~2!"
if defined var (
set "var=!var:^=^^!"
set "var=!var:"=^^"!"
set "var=!var:&=^&!"
set "var=!var:|=^|!"
set "var=!var:>=^>!"
set "var=!var:<=^<!"
)
set "%~1=!var!"
exit /b