Function

f_closfd invokes the fcntl callable service to close a range of file descriptors.

Parameters

fd

The file descriptor (a number) for a file. This is the first file descriptor to be closed.

fd2

The file descriptor (a number) for a file, which must be greater than or equal to fd. If a -1 is specified for fd2, all file descriptors greater than or equal to fd are closed.

Usage notes

1. A process can use f_closfd to close a range of file descriptors. fd2 must be greater than or equal to fd, or it can also be -1, which indicates that all file descriptors greater than or equal to fd are to be closed.
2. Use of f_closfd is meant to be consistent with the close callable service. You cannot close file descriptors that could not also be closed using the close service.
3. When a file descriptor cannot be closed, it is considered an error, but the request continues with the next file descriptor in the range. File descriptors that are not in use are ignored.