system() function

[vibhu mishra]

i m trying to run a mp3 file on dosbox plateform by c .i put the following code in to the batch file
start c:\xyz.mp3 and trying to call this as system("c:/a.bat"), the system funtion is returing 0 but it is not running it. But the same code working well on Cmd . i m using win 7 32 bit..

[cgeier]

The following works for me:

#include <cstdlib>

//use 8.3 filename and directory name format
//my file is in "c:\batch scripts\startmp3.bat"

//To get the 8.3 directory name:
//in cmd window run > dir "c:\" /x | find /i "batch scripts"


system("c:\\batchs~1\\startmp3.bat"); //make sure to escape '\'

//should also be able to use:
//system("c:/batchs~1/startmp3.bat");

See How Windows Generates 8.3 File Name from Long File Names

The important thing is to use 8.3 (DOS) filenames.

[N1GHTS]

Note that system() returns a program status code. It is good practice to use this value for error handling.

[vibhu mishra]

when i m using system("c:\xyz.bat"); it is returning zero and print a message "Illegal commanad:c:\xyz.bat". But on using system("c:/xyz.bat"); it is not showing illegal command statement but also not running.......

[N1GHTS]

Try this:

int Status = system("cmd.exe /c c:/xyz.bat");

Or on Windows 64 bit:

int Status = system("%windir%\\Sysnative\\cmd.exe /c c:/xyz.bat");

I'm not on Windows so I can't test this for you. Can't hurt.

Reference

[cgeier]

I discovered another solution that lets you avoid 8.3 filenames. Use double-quotes. But you need to escape them with a '\'.

#include <cstdlib>

int returnVal = 0;

//need to put quotes if dir or filename contains spaces
//need to escape quotes
returnVal = system("\"c:/batch scripts/startmp3.bat\"");

if (returnVal != 0)
{
    printf("An error occurred while running the command.  (%i)\n",returnVal);
}//if
else
{
    printf("Command executed successfully.\n",returnVal);
}//else

return returnVal;

Here is another resource that may be of use:
How to spawn console processes with redirected standard handles

[cgeier]

If using '\', you may need to escape it. So use system("c:\\xyz.bat"); instead of system("c:\xyz.bat");

[cgeier]

Can you post your code? Also, what program are you trying to use to play the mp3? Check the Windows default: Control Panel (View by: Large icons) => Default programs => Associate a file type or protocol with a program. Look for "mp3." What is the current default?

[vibhu mishra]

i m just trying to invoke a batch file by using system() function. Batch file containing start c:\abc.mp3 and i m passing this batch file to system("c:/xyz.bat"); both mp3 and batch file in the same directory , system is returning 0 but the mp3 file is not playing.....

[Ancient Dragon]

Sounds like the console window is closing and killing the mp3. Add a PAUSE in the batch file after the line that plays the mp3 to keep the console window open while the mp3 plays.

[cgeier]

I know what you're trying to do. But I want to see how you are doing it, because obviously what you are doing isn't working for you. Without the code I can't help any further. Also include the batch (.bat) file. What C compiler are you using? Also a screen shot of the error may be helpful.