How to call an external program with parameters?

When you call CreateProcess(), System(), etc., make sure you double quote your file name strings (including the command program filename) in case your file name(s) and/or the fully qualified path have spaces otherwise the parts of the file name path will be parsed by the command interpreter as separate arguments.

system("\"d:some path\\program.exe\" \"d:\\other path\\file name.ext\"");

For Windows it is recommended to use CreateProcess(). It has messier setup but you have more control on how the processes is launched (as described by Greg Hewgill). For quick and dirty you can also use WinExec().
(system() is portable to UNIX).

When launching batch files you may need to launch with cmd.exe (or command.com).

WinExec("cmd \"d:some path\\program.bat\" \"d:\\other path\\file name.ext\"",SW_SHOW_MINIMIZED);

(or SW_SHOW_NORMAL if you want the command window displayed ).

Windows should find command.com or cmd.exe in the system PATH so in shouldn’t need to be fully qualified, but if you want to be certain you can compose the fully qualified filename using CSIDL_SYSTEM (don’t simply use C:\Windows\system32\cmd.exe).

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