[khajalid]

I m making an project in which i have to access a file from from 2 programs. One program is in vc++ and other in php.In this i need to lock the file when one of the program is using it.So, when php is using the file, file get locked but if in the mean time when file is locked if vc++ needs to access it it must check whether the file is already been locked or not. so how to check for it using vc++.

-regards.
Ankush Gupta.

[shabbir]

Use the Opening Flags for Exclusive Read/Write permission

[khajalid]

I m a student so can u tell me How to implement that?

[shabbir]

Read / Write files have the needed modes for that and see the File opening API in both.

How you are trying to read the file in both and I would tell you the modes.

[khajalid]

i m implementing it as
fp=fopen("login.txt","r");

[shabbir]

I assume you are mentioning this in PHP and try using this flock API . ( http://in.php.net/flock )

For C++ also let me know the API you are using ?

[khajalid]

no, it is in c and i need to check the lock through c which was implemented by php.

[khajalid]

Also i need to lock file through c after checking if it is unlocked.
i have nthg to do with php.i is not my nwork.

[shabbir]

If you are using Linux you can do is change the chmod of the file to the needed values so others can only access it as per your permission set.

If you are using Windows then try using _open function