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CLOSEFROM(2) FreeBSD System Calls Manual CLOSEFROM(2)
NAME
closefrom, close_range - delete open file descriptors
LIBRARY
Standard C Library (libc, -lc)
SYNOPSIS
#include <unistd.h>
void
closefrom(int lowfd);
int
close_range(u_int lowfd, u_int highfd, int flags);
DESCRIPTION
The closefrom() system call deletes all open file descriptors greater
than or equal to lowfd from the per-process object reference table. Any
errors encountered while closing file descriptors are ignored.
The close_range() system call deletes all open file descriptors between
lowfd and highfd inclusive, clamped to the range of open file
descriptors. Any errors encountered while closing file descriptors are
ignored. Supported flags:
CLOSE_RANGE_CLOEXEC Set the close-on-exec flag on descriptors in the
range instead of closing them.
RETURN VALUES
Upon successful completion, close_range() returns a value of 0.
Otherwise, a value of -1 is returned and the global variable errno is set
to indicate the error.
ERRORS
The close_range() system call will fail if:
[EINVAL] The highfd argument is lower than the lowfd argument.
[EINVAL] An invalid flag was set.
SEE ALSO
close(2)
HISTORY
The closefrom() function first appeared in FreeBSD 8.0.
FreeBSD 14.0-RELEASE-p6 March 3, 2022 FreeBSD 14.0-RELEASE-p6