How to know whether a file is open?

I want to get whether a file is open to be written by other program. How can i do that?

[94 byte] By [youhaodiyia] at [2007-11-27 7:37:13]

# 1

For what purpose?

ejpa at 2007-7-12 19:17:45 >

# 2

When my program read a file and at the same time another program is modifying this file, my program will get a incorrent content.

youhaodiyia at 2007-7-12 19:17:45 >

# 3

So write-lock the file.

ejpa at 2007-7-12 19:17:45 >

# 4

If I lock the file, other program will not read or change the file. I want to make my program to wait untill no other programs open the file.

youhaodiyia at 2007-7-12 19:17:45 >

# 5

Have the other program write lock the file; have this program wait for the lock; and then have it set a read-only lock if necessary.

ejpa at 2007-7-12 19:17:45 >

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