How can I pass arguments to a batch file?

Another useful tip is to use %* to mean "all". For example:

echo off
set arg1=%1
set arg2=%2
shift
shift
fake-command /u %arg1% /p %arg2% %*

When you run:

test-command admin password foo bar

the above batch file will run:

fake-command /u admin /p password admin password foo bar

I may have the syntax slightly wrong, but this is the general idea.

Here's how I did it:

@fake-command /u %1 /p %2

Here's what the command looks like:

test.cmd admin P@55w0rd > test-log.txt

The %1 applies to the first parameter the %2 (and here's the tricky part) applies to the second. You can have up to 9 parameters passed in this way.

If you want to intelligently handle missing parameters you can do something like:

IF %1.==. GOTO No1
IF %2.==. GOTO No2
... do stuff...
GOTO End1

:No1
  ECHO No param 1
GOTO End1
:No2
  ECHO No param 2
GOTO End1

:End1

Accessing batch parameters can be simple with %1, %2, ... %9 or also %*,
but only if the content is simple.

There is no simple way for complex contents like "&"^&, as it's not possible to access %1 without producing an error.

set  var=%1
set "var=%1"
set  var=%~1
set "var=%~1"

The lines expand to

set  var="&"&
set "var="&"&"
set  var="&"&
set "var="&"&"

And each line fails, as one of the & is outside of the quotes.

It can be solved with reading from a temporary file a remarked version of the parameter.

@echo off
SETLOCAL DisableDelayedExpansion

SETLOCAL
for %%a in (1) do (
    set "prompt="
    echo on
    for %%b in (1) do rem * #%1#
    @echo off
) > param.txt
ENDLOCAL

for /F "delims=" %%L in (param.txt) do (
  set "param1=%%L"
)
SETLOCAL EnableDelayedExpansion
set "param1=!param1:*#=!"
set "param1=!param1:~0,-2!"
echo %%1 is '!param1!'

The trick is to enable echo on and expand the %1 after a rem statement (works also with %2 .. %*).
So even "&"& could be echoed without producing an error, as it is remarked.

But to be able to redirect the output of the echo on, you need the two for-loops.

The extra characters * # are used to be safe against contents like /? (would show the help for REM).
Or a caret ^ at the line end could work as a multiline character, even in after a rem.

Then reading the rem parameter output from the file, but carefully.
The FOR /F should work with delayed expansion off, else contents with "!" would be destroyed.
After removing the extra characters in param1, you got it.

And to use param1 in a safe way, enable the delayed expansion.

Yep, and just don't forget to use variables like %%1 when using if and for and the gang.

If you forget the double %, then you will be substituting in (possibly null) command line arguments and you will receive some pretty confusing error messages.

How can I pass arguments to a batch file?

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