Is the gettimeofday function thread safe in Linux?

The current time must be stored globally in order for gettimeofday to work, however I开发者_StackOverflow am not sure if the function modifies any global state so that concurrent execution is undefined.

gettimeofday is thread safe.

The (posix) functions listed here might not be, gettimeofday is not one of them.

Yes, it is thread-safe. The only data it modifies is in the structures you pass pointers to, so an implementation that wasn't thread-safe would have to be doing something spooky.

Best of luck on your project.

In glibc the gettimeofday(2) is a simple wrapper around a system call (it's a vsyscall actually). No data is touched in the userland. It is thread-safe.

No data is modified with this call. You just get a copy. Hence its completely thread safe.