Thread: Flushing of data is not proper.

Hi all,

I am Going through a problem on files.
Environment of problem is, I have opened some files for logging.
Now when program is going through load testing then it flush Log data in various file(which i have opened in my program, and one file is opened by Apache as error_log).

But sometime it happenes, My own file data get flushed into error_log of apache.

Can anybody tell me why this is so?

So let me get this straight...you have error_log opened, your write data to it and flush it, and you're surprised that it's showing up in the file?

Linux doesn't have inherent file sharing prohibitions like Windows does if that's what you're confused about. Linux will let 2 different programs write to the same file without complaining which might lead to weird results.

Originally Posted by itsme86

So let me get this straight...you have error_log opened, your write data to it and flush it, and you're surprised that it's showing up in the file?

Linux doesn't have inherent file sharing prohibitions like Windows does if that's what you're confused about. Linux will let 2 different programs write to the same file without complaining which might lead to weird results.

Thats right that two different programs can write in same file. But tell me is this possible that two different file descriptor pointing to two different file write data into one of them only.

We'd have to see your code to see what's wrong.

I don't think anything's wrong; I think the OP wants to know why two programs can write to the same file without bad results.

If you're trying to prevent that, you might try opening the file as exclusive (not with fopen; maybe with open).

is this possible that two different file descriptor pointing to two different file write data into one of them only.

That sounds more to me like he's trying to write to 2 different files, but all of the data is going into one of them.

Yeah, you're right. But that doesn't make much sense, unless one of the files is a link to the other. Or one of the files is one of the standard streams, and it's being redirected.