CAP_ENVL(3C)CAP_ENVL(3C)NAME
cap_envl, cap_envp - ensure sufficient process privilege
SYNOPSIS
#include <sys/capability.h>
int cap_envl(int flags, ... /* cap_value_t */)
int cap_envp(int flags, size_t ncap, const cap_value_t *caps)
DESCRIPTIONcap_envl and cap_envp ensure that the calling process will have
sufficient privilege to perform actions requiring the specified
capabilities. If the desired and current capability sets are different
and if the desired capability set can be obtained because the process has
the CAP_SETPCAP capability, then the capabilities in the desired will be
acquired.
cap_envl accepts a variable argument list of capability values,
terminated by an argument of 0 (or CAP_NOT_A_CID).
cap_envp accepts a counted array of capability values, whose size is
specified by ncap and whose address is caps.
cap_envl and cap_envp also understand several flags, which may be
bitwise-ored together:
CAP_ENV_SETUID If successful, set the process' effective userid to its
real userid.
CAP_ENV_RECALC If successful, set the CAP_FLAG_PURE_RECALC capability
flag.
cap_envl and cap_envp will return an error if they cannot give the
calling process privilege equivalent to having the capabilities specified
in caps, or if the optional actions specified by flags were not
successful.
RETURN VALUEScap_envl and cap_envp return 0 if successful, or -1 on error.
ERRORS
cap_envl:
EINVAL One of the specified capabilities is invalid.
EPERM The calling process has insufficient privilege to perform
privileged actions requiring the requested capabilities.
cap_envp:
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CAP_ENVL(3C)CAP_ENVL(3C)
EINVAL ncap is 0, caps is NULL, or one of the specified
capabilities is invalid.
EPERM The calling process has insufficient privilege to perform
privileged actions requiring the requested capabilities.
SEE ALSOcap_set_proc(3c), capabilities(4).
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