Locking a file by same process

[Tharangini Karthikeyan]

Hi
My requirement is , when I give two subsequent open statements opening the same file I want my second open statement to fail saying that the file is already opened.ie. I don't want sharing facility.In AIX we have a flag O_NSHARE in open statement which solves my problem ,In HP 11 this provision is not there.
So if anyone knew please do give me the solution as early as possible.

Regards
Tharangini

[Wodisch]

Hi,

under whihch UID do you run your program? Usually "root" does not care about file and record locks...

Just an idea,
Wodisch

[A. Clay Stephenson]

HP-UX is not AIX and in fact you are using a non-standard UNIX feature. File locking has always been the responsibility of the programmer. You can change your code to use lockf() to test for locks.

[A. Clay Stephenson]

Plan B.

If this is the same process, why not simply use a variable to indicate that you already have the file open.