CLOSEFROM(2) BSD System Calls Manual CLOSEFROM(2)
closefrom -- delete many descriptors
The closefrom() call deletes all descriptors numbered fd and higher from
the per-process file descriptor table. It is effectively the same as
calling close(2) on each descriptor.
Upon successful completion, the value 0 is returned; otherwise the
value -1 is returned and the global variable errno is set to indicate the
closefrom() will fail if:
[EBADF] fd is greater than all open file descriptors.
[EINTR] An interrupt was received.
closefrom() is a BSD and Solaris extension.
The closefrom() call first appeared in OpenBSD 3.5.
BSD March 3, 2015 BSD