Subroutines in batch files

Question

Given the following code:

@Echo off ECHO Start ECHO Calling SUB_A CALL :SUB_A ECHO Calling SUB_B CALL :SUB_B  :SUB_A     ECHO In SUB_A     GOTO:EOF  :SUB_B     ECHO In SUB_B     GOTO:EOF  ECHO End 

I expect this output:

Start Calling SUB_A In SUB_A Calling SUB_B In SUB_B End 

But I get this:

Start Calling SUB_A In SUB_A Calling SUB_B In SUB_B In SUB_A 

What am I doing wrong here?

Answer 1

If you want to return from a CALL, you use EXIT command with /B argument (as "EXIT" alone will terminate the batch file).

For example:

CALL :SUB_ONE CALL :SUB_TWO  GOTO :EOF  :SUB_ONE ECHO Hello from one EXIT /B  :SUB_TWO ECHO Hello from two EXIT /B  :EOF 

Answer 2

The line CALL :SUB_B returns, the script proceeds to the next few lines:

:SUB_A           # no effect from this one ECHO In SUB_A    # prints message 

You need to insert a GOTO:EOF after the call if you want it to stop there.

Batch files are not structured programs; they are a sequence of instructions with some BASIC-like facility for GOTO and CALL.