INTELLIGENT WORK FORUMS
FOR COMPUTER PROFESSIONALS

Member Login

Come Join Us!

Are you a
Computer / IT professional?
Join Tek-Tips now!

Talk With Other Members
Be Notified Of Responses
To Your Posts
Keyword Search
One-Click Access To Your
Favorite Forums
Automated Signatures
On Your Posts
Best Of All, It's Free!

*Tek-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

LINK TO THIS FORUM!

Tek-Tips LinkedIn^® Group

Join our
LinkedIn^® Group!

Hook up with past and present colleagues and classmates quickly.

Partner With Us!

"Best Of Breed" Forums Add Stickiness To Your Site

(Download This Button Today!)

Feedback

"...your web site's great! I've been using this system for almost a year now and find it really, really helpful. The people have been helpful in answering just about any question you post in the forums..."

More...

Geography

Where in the world do Tek-Tips members come from?

Click Here To Find Out!

Tek-Tips Shirts!

Get your
Tek-Tips Forums
SWAG here!

Home > Forums > Programmers > Languages > C Forum

memory allocated within function and passed out of it

Read More Threads Like This One

lehe (Programmer)

18 Jul 08 20:00

Hi,
I am asking for using "malloc" to allocate memory within a self-written function and then pass on to the outside of the function. I did it this way but guess that it might be the reason that caused run-time memory error. Could you please point out if it is wrong and give the correct way? Thanks in advance!

void main(){
int* ptr;
myfun(&ptr);
free(ptr);
}

void myfun(int**p){
int num;
// read the value of "num" from some file...
*p=(int*)malloc(num*sizeof(int));
}

cpjust (Programmer)

18 Jul 08 23:26

There are 2 things wrong with your code that I can see:

1. There's no such thing as void main(). main() returns an int. See: http://faq.cprogramming.com/cgi-bin/smartfaq.cgi?answer=1044841143&id=1043284376

2. You shouldn't cast malloc(). See: http://faq.cprogramming.com/cgi-bin/smartfaq.cgi?answer=1047673478&id=1043284351

Are you having any problems with the code now, or are you just wondering if it's correct?

lehe (Programmer)

19 Jul 08 10:04

Thanks for pointing out what I was not unware of.

Besides that, let's move back to my original question. Will it cause runtime memory error using "malloc" to allocate memory within a function and then pass on to its outside?

ArkM (IS/IT--Management)

19 Jul 08 10:34

Don't worry. You may use a pointer to allocated memory here, there and everywhere.

Reply To This Thread

Posting in the Tek-Tips forums is a member-only feature.

Click Here to join Tek-Tips and talk with other members!

Back To Forum

Back To C