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libcap(3)


NAME

   cap_clear,  cap_clear_flag,  cap_compare,  cap_copy_ext,  cap_copy_int,
   cap_free,  cap_from_name,  cap_from_text,   cap_get_fd,   cap_get_file,
   cap_get_flag,   cap_get_pid,  cap_get_proc,  cap_set_fd,  cap_set_file,
   cap_set_flag,   cap_set_proc,   cap_size,   cap_to_name,   cap_to_text,
   cap_get_pid, cap_dup - capability data object manipulation

SYNOPSIS

   #include <sys/capability.h>

   int cap_clear(cap_t cap_p);

   int cap_clear_flag(cap_t cap_p, cap_flag_t flag);

   int cap_compare(cap_t cap_a, cap_t cap_b);

   ssize_t cap_copy_ext(void *ext_p, cap_t cap_p, ssize_t size);

   cap_t cap_copy_int(const void *ext_p);

   int cap_free(void *obj_d);

   int cap_from_name(const char *name, cap_value_t *cap_p);

   cap_t cap_from_text(const char *buf_p);

   cap_t cap_get_fd(int fd);

   cap_t cap_get_file(const char *path_p);

   int cap_get_flag(cap_t cap_p, cap_value_t cap,
                    cap_flag_t flag, cap_flag_value_t *value_p);

   #include <sys/types.h>
   cap_t cap_get_pid(pid_t pid);

   cap_t cap_get_proc(void);

   int cap_set_fd(int fd, cap_t caps);

   int cap_set_file(const char *path_p, cap_t cap_p);

   int cap_set_flag(cap_t cap_p, cap_flag_t flag, int ncap,
                    const cap_value_t *caps, cap_flag_value_t value);
   int cap_set_proc(cap_t cap_p);

   ssize_t cap_size(cap_t cap_p);

   char *cap_to_name(cap_value_t cap);

   char *cap_to_text(cap_t caps, ssize_t *length_p);

   cap_t cap_get_pid(pid_t pid);

   cap_t cap_dup(cap_t cap_p);

   Link with -lcap.

DESCRIPTION

   These  functions work on a capability state held in working storage.  A
   cap_t holds information about the capabilities in  each  of  the  three
   sets,  Permitted, Inheritable, and Effective.  Each capability in a set
   may be clear (disabled, 0) or set (enabled, 1).

   These functions work with the following data types:

   cap_value_t       identifies a capability, such as CAP_CHOWN.

   cap_flag_t        identifies one of the three flags associated  with  a
                     capability  (i.e.,  it  identifies  one  of the three
                     capability sets).  Valid values  for  this  type  are
                     CAP_EFFECTIVE, CAP_INHERITABLE or CAP_PERMITTED.

   cap_flag_value_t  identifies  the  setting  of  a particular capability
                     flag (i.e, the value  of  a  capability  in  a  set).
                     Valid  values  for  this  type  are  CAP_CLEAR(0)  or
                     CAP_SET(1).

RETURN VALUE

   The return value is  generally  specific  to  the  individual  function
   called.  On failure, errno is set appropriately.

CONFORMING TO

   These  functions are as per the withdrawn POSIX.1e draft specification.
   The  following  functions  are  Linux   extensions:   cap_clear_flag(),
   cap_compare(), cap_from_name(), cap_to_name(), and cap_compare().

SEE ALSO

   cap_clear(3),   cap_copy_ext(3),   cap_from_text(3),   cap_get_file(3),
   cap_get_proc(3), cap_init(3), capabilities(7), getpid(2) capsh(1)

                              2008-07-29                         LIBCAP(3)



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