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Answer 1

+1 A:

Don't use start but cmd /c.

ETA: As Chris Jester-Young notes in a comment, this will then look like

execlp("cmd", "/c", batchfile, static_cast<char*>(0))

in your code.

ETA 2: It appears that you don't even need cmd there. Just the batch file as command should suffice. Since start worked and start is a built-in command of cmd.exe there has to be an instance of cmd running for your original invocation to work. So just execute the batch file as if it were the program, this should suffice.

Joey 2010-02-01 14:00:58

Which, here, translates to `execlp("cmd", "/c", batchfile, static_cast<char*>(0))`.

Chris Jester-Young 2010-02-01 14:03:54

@Chris, thanks. My experience with C++ and C is quite limited. The underlying problem was pretty obvious, though.

Joey 2010-02-01 14:07:05

execlp() API says, first argument should be path of the file to execute , does this interpret cmd to cmd.exe ?

Venkat 2010-02-01 14:11:43

@Venkat: Try it out. I honestly have no idea. You can put cmd.exe in there too if you like.

Joey 2010-02-01 14:12:31

@Johannes: No worries. If you're curious, read http://www.opengroup.org/onlinepubs/9699919799/functions/exec.html for more info on the various `exec*` functions. The `static_cast<char*>(0)` is the C++ way of expressing `(char *) 0` which is listed in their documentation.

Chris Jester-Young 2010-02-01 14:13:33

@Venkat: You may have to use `cmd.exe`, yes. I haven't done enough Windows programming to tell you one way or the other. (Cygwin will automatically do `.exe` resolution for you, but can't speak about other Windows programming environments.)

Chris Jester-Young 2010-02-01 14:14:38

@Venkat: On second thought, you only need the batch file directly; see the second edit.

Joey 2010-02-01 14:15:52

@Johannes: Huh, how interesting (that `exec*` can execute shell builtins, at least for the OP's environment). I certainly do not expect the same to work in Unix; there, using `sh -c ...` is required. :-P

Chris Jester-Young 2010-02-01 14:17:27

@Chris: That was inferred from the OP's original usage. But I faintly remember some docs by MS that said so. But batch files can be run like normal programs in any case, afaik; but especially so if there is a shell already executing that ;-)

Joey 2010-02-01 14:21:28

@johannes and @chris , the only function call working is system() and not the execl and execlp are not at all executing... and also i would like to execute the batch file in background.... user should not be prompted with new command screen nor any popup should appear.

Venkat 2010-02-01 14:26:21

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execute a batch file from a program

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