CAP_INIT(3) Linux Programmer's Manual CAP_INIT(3)NAME
cap_init, cap_free, cap_dup - capability data object storage management
SYNOPSIS
#include <sys/capability.h>
cap_t cap_init(void);
int cap_free(void *obj_d);
cap_t cap_dup(cap_t cap_p);
USAGE
cc ... -lcap
DESCRIPTION
The capabilities associated with a file or process are never edited
directly. Instead, working storage is allocated to contain a represen‐
tation of the capability state. Capabilities are edited and manipu‐
lated only within this working storage area. Once editing of the capa‐
bility state is complete, the updated capability state is used to
replace the capability state associated with the file or process.
cap_init creates a capability state in working storage and return a
pointer to the capability state. The initial value of all flags are
cleared. The caller should free any releasable memory, when the capa‐
bility state in working storage is no longer required, by calling
cap_free with the cap_t as an argument.
cap_free liberates any releasable memory that has been allocated to the
capability state identified by obj_d. The obj_d argument may identify
either a cap_t entity, or a char * entity allocated by the cap_to_text
function.
cap_dup returns a duplicate capability state in working storage given
by the source object cap_p, allocating any memory necessary, and
returning a pointer to the newly created capability state. Once dupli‐
cated, no operation on either capability state affects the other in any
way.
RETURN VALUEcap_init and cap_dup return a non-NULL value on success, and NULL on
failure.
cap_free returns zero on success, and -1 on failure.
On failure, errno(3) is set to EINVAL, or ENOMEM.
CONFORMING TO
These functions are specified by POSIX.1e.
SEE ALSOcap_clear(3), cap_copy_ext(3), cap_from_text(3), cap_get_file(3),
cap_get_proc(3)
26th May 1997 CAP_INIT(3)