What happens fwrite/fread at the same time?


 
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Old 02-15-2011
What happens fwrite/fread at the same time?

Hello,

I have a question about what happens when I copy the file which is being written by another process on Solaris 9/SPARC, UFS file system.

in particular, I want to know what happens while some process is reading the file using fread or mmap, another process try to write something on the exactly same place where is read by other process.

in the situation described above, does fwrite causes error? or both system call suceeds?

If you know there is some document or specification defines about confliction of read/write/mmap, please tell me.

(sorry if my English or manner is not good, I've never been post a question in these kind of forums)

Thanks.
 
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