Its with NSTask.
NSTask *task = [NSTask new];
[task setLaunchPath:@"/usr/bin/env"];
[task setArguments:[NSArray arrayWithObjects:@"diskutil", @"eraseVolume", @"ms-dos", nmToPD, pathToPD,nil]];
NSPipe *pipe = [NSPipe pipe];
[task setStandardOutput:pipe];
[task launch];
[task waitUntilExit];