access problem with files

[venkatvasa]

hai all,

we are working on fork() for first time. we are able to work it out partly.

i have two process created with the help of fork().

In each process, i call a function with argument int value and file pointer.

The results of the function should have to written in the file corresponding to the file pointer in the function.

when i tried to do this, only the entries in the first file are being made and for the second file error has occurred.

how can i pass only the address of file to the function from main and can able to make entries into two files simultaneously.

i have tried these combinations,

in main,
func(1,fileprt);

in func,

void func(int i, file *file1){
fprintf(file1,"%d",x);
}

[arnaudk]

I don't think you can write simultaneously to the same file from two different threads without creating a race condition. The responsibility of writing to a file should be delegated to a single thread, or use two separate files, or ensure only one thread accesses the file at a time.

[venkatvasa]

I don't think you can write simultaneously to the same file from two different threads without creating a race condition. The responsibility of writing to a file should be delegated to a single thread, or use two separate files, or ensure only one thread accesses the file at a time.

hai arnaudk,
Thanks for taking time out for replying to my problem.
actually i'm writing the results of the two processes into two different files.
sorry, i haven't made that point clear in my description of the problem.
Anyways, my problem is resolved.