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Where is O_SHLOCK and O_EXLOCK defined?



I am trying to use 'open()' with some file control flags. According to Linux manual of 'open()':

int open(const char *path, int flags, ...);
......
The flags specified are formed by or’ing the following values

O_RDONLY open for reading only
O_WRONLY open for writing only
O_RDWR open for reading and writing
O_NONBLOCK do not block on open
O_APPEND append on each write
O_CREAT create file if it does not exist
O_TRUNC truncate size to 0
O_EXCL error if create and file exists
O_SHLOCK atomically obtain a shared lock
O_EXLOCK atomically obtain an exclusive lock
O_DIRECT eliminate or reduce cache effects
O_FSYNC synchronous writes
O_SYNC synchronous writes
O_NOFOLLOW do not follow symlinks
O_NOCTTY don’t assign controlling terminal

But when I tried to use O_SHLOCK or O_EXLOCK bits, I got compilation errors:
error: ‘O_SHLOCK’ was not declared in this scope
I check 'fcntl.h' and there is no such bit definition.

Anyone knows where these bits are defined.
 
Alex


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