CAPGET(2) Linux Programmer's Manual CAPGET(2)
NAME
capget, capset - set/get process capabilities
SYNOPSIS
#undef_POSIX_SOURCE
#include<sys/capability.h>
intcapget(cap_user_header_t header,cap_user_data_t data);
intcapset(cap_user_header_t header,constcap_user_data_t data);
DESCRIPTION
As of Linux 2.2, the power of the superuser (root) has been partitioned
into a set of discrete capabilities. Every process has a set of effec-
tive capabilities identifying which capabilities (if any) it may cur-
rently exercise. Every process also has a set of inheritable capabili-
ties that may be passed through an execve(2) and a set of permitted
capabilites that it can make effective or inheritable.
These two functions are the raw kernel interface for getting and set-
ting capabilities. Not only are these system calls specific to Linux,
but the kernel API is likely to change and use of these functions (in
particular the format of the cap_user_*_t types) is subject to change
with each kernel revision.
The portable interfaces are cap_set_proc(3) and cap_get_proc(3); if
possible you should use those interfaces in applications. If you wish
to use the Linux extensions in applications, you should use the easier-
to-use interfaces capsetp(3) and capgetp(3).
RETURNVALUE
On success, zero is returned. On error, -1 is returned, and errno is
set appropriately.
ERRORS
EINVAL One of the arguments was invalid.
EPERM An attempt was made to add a capability to the Permitted set, or
to set a capability in the Effective or Inheritable sets that is
not in the Permitted set.
FURTHERINFORMATION
The portable interface to the capability querying and setting functions
is provided by the libcap library and is available from here:
ftp://linux.kernel.org/pub/linux/libs/security/linux-privs
SEEALSO
capabilities(7)
Linux 2.2 1999-09-09 CAPGET(2)
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