close_checked

This wraps the close call.

In case of error, errno will be preserved, but the error will also be stored as a Error in throws. In case of success, errno is undefined.

Besides using Error, there is another major reason to prefer this function over the call provided by the system; on Unix, it will attempt to correctly handle eintr, which has platform-specific semantics.

It is a bug to call this function with an invalid file descriptor.

Since 2.76, this function is guaranteed to be async-signal-safe if (and only if) throws is null and fd is a valid open file descriptor.

Parameters:

fd	A file descriptor

Returns:

true on success, false if there was an error.