libcap(3) — Linux manual page


LIBCAP(3)               Linux Programmer's Manual              LIBCAP(3)

NAME         top

       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         top

       #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         top

       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:

              identifies a capability, such as CAP_CHOWN.

              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

              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         top

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

CONFORMING TO         top

       These functions are as per the withdrawn POSIX.1e draft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

REPORTING BUGS         top

       The libcap library is distributed from where the release
       notes may already cover recent issues.  Please report newly
       discovered bugs via:

SEE ALSO         top

       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) and libpsx(3).

COLOPHON         top

       This page is part of the libcap (capabilities commands and
       library) project.  Information about the project can be found at
       ⟨⟩.  If you
       have a bug report for this manual page, send it to (please put "libcap" in the Subject line).
       This page was obtained from the project's upstream Git repository
       ⟨⟩ on
       2021-08-27.  (At that time, the date of the most recent commit
       that was found in the repository was 2021-08-25.)  If you
       discover any rendering problems in this HTML version of the page,
       or you believe there is a better or more up-to-date source for
       the page, or you have corrections or improvements to the
       information in this COLOPHON (which is not part of the original
       manual page), send a mail to

                               2021-03-06                      LIBCAP(3)

Pages that refer to this page: capsh(1)prctl(2)cap_clear(3)cap_copy_ext(3)cap_from_text(3)cap_get_file(3)cap_get_proc(3)cap_iab(3)cap_init(3)cap_launch(3)libpsx(3)capabilities(7)