change a copy of a sound file name before email it - objective-c

Question

I am sending a sound file to email , but i want to change its name just for the email.
lets say i take some sound.caf , in my folder , i want to leave its name just like that ,but to take a copy of it ,change its name, and then send it.
i will show how i send email, and i need the simplest way to change the file name without affecting the original :
//send email log-------------------------
NSLog(#"mail");
[[CCDirector sharedDirector] pause];
picker = [[MFMailComposeViewController alloc] init];
picker.mailComposeDelegate = self;
NSArray *toRecipients = [NSArray arrayWithObject:#"your email"];
[picker setToRecipients:toRecipients];
NSString *sound=[NSString stringWithFormat:#"sound%d.caf",[memoryInstnace getSoundToEdit]]; //here, i need to change the name of the copy .
NSArray *paths2 = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *dataPath = [[paths2 objectAtIndex:0] stringByAppendingPathComponent:sound];
NSData *data = [NSData dataWithContentsOfFile:dataPath];
[picker addAttachmentData:data mimeType:#"caf" fileName:sound];//
NSString *emailBody = #"my sound ";
[picker setMessageBody:emailBody isHTML:NO];
[picker setSubject:#" new message "];
//display the view
[[[CCDirector sharedDirector] view] addSubview:picker.view];
//[[CCDirector sharedDirector] stopAnimation];
[[CCDirector sharedDirector] pause];

Answer 1

Simply put the file name you like here:
[picker addAttachmentData:data mimeType:#"caf" fileName:myFileName];
and it will be received as myFileName instead of sound. Indeed, you are just attaching some data to your email message; this is unrelated to where the data came from (it could be a file, the network, etc); when attaching, you specify the name under which the data will be recognized as an attachment on the receiving end.