pr_capbset_drop(2const) - BetterMan

pr_capbset_drop(2const)

drop a capability from the calling thread's capability bounding set

distropkg manpages-dev@6.9.1-1dataset 2026-04-01T06:19:02Z+debian+ec4110e+mandoc:1.14.6-4

Synopsis

#include <linux/prctl.h>
  /* Definition of 
PR_*
 constants */
#include <sys/prctl.h>
int prctl(PR_CAPBSET_DROP, long 
cap
);

—

Options · 3

EINVAL	File capabilities are not enabled in the kernel.
EINVAL	cap does not specify a valid capability.
EPERM	The caller does not have the CAP_SETPCAP capability.

NAME

PR_CAPBSET_DROP - drop a capability from the calling thread's capability bounding set

LIBRARY

Standard C library (libc, -lc)

SYNOPSIS

bash

#include <linux/prctl.h>\n  /* Definition of \nPR_*\n constants */
\n#include <sys/prctl.h>

bash

int prctl(PR_CAPBSET_DROP, long \ncap\n);

DESCRIPTION

Drop the capability specified by cap from the calling thread's capability bounding set. Any children of the calling thread will inherit the newly reduced bounding set.

RETURN VALUE

On success, 0 is returned. On error, -1 is returned, and errno is set to indicate the error.

ERRORS

EINVAL: File capabilities are not enabled in the kernel.
EINVAL: cap does not specify a valid capability.
EPERM: The caller does not have the CAP_SETPCAP capability.

VERSIONS

A higher-level interface layered on top of this operation is provided in the libcap(3) library in the form of cap_drop_bound(3).

STANDARDS

Linux.

HISTORY

Linux 2.6.25.