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DNV(9) FreeBSD Kernel Developer's Manual DNV(9) NAME dnvlist_get, dnvlist_take - API for getting name/value pairs. Nonexistent pairs do not raise an error. LIBRARY Name/value pairs library (libnv, -lnv) SYNOPSIS #include <sys/dnv.h> bool dnvlist_get_bool(const nvlist_t *nvl, const char *name, bool defval); uint64_t dnvlist_get_number(const nvlist_t *nvl, const char *name, uint64_t defval); char * dnvlist_get_string(const nvlist_t *nvl, const char *name, const char *defval); nvlist_t * dnvlist_get_nvlist(const nvlist_t *nvl, const char *name, nvlist_t *defval); int dnvlist_get_descriptor(const nvlist_t *nvl, const char *name, int defval); void * dnvlist_get_binary(const nvlist_t *nvl, const char *name, size_t *sizep, void *defval, size_t defsize); bool dnvlist_take_bool(const nvlist_t *nvl, const char *name, bool defval); uint64_t dnvlist_take_number(const nvlist_t *nvl, const char *name, uint64_t defval); char * dnvlist_take_string(const nvlist_t *nvl, const char *name, const char *defval); nvlist_t * dnvlist_take_nvlist(const nvlist_t *nvl, const char *name, nvlist_t *defval); int dnvlist_take_descriptor(const nvlist_t *nvl, const char *name, int defval); void * dnvlist_take_binary(const nvlist_t *nvl, const char *name, size_t *sizep, void *defval, size_t defsize); DESCRIPTION nvlists, descriptors, binaries, or arrays must not be modified by the user. They still belong to the nvlist. If the nvlist is in an error state, attempts to use any of these functions will cause the program to abort. The dnvlist_take family of functions returns the value associated with the specified name and removes the element from the nvlist. If an element of the supplied name does not exist, the value provided in defval is returned. When the value is a string, binary, or array value, the caller is responsible for freeing returned memory with free(3). When the value is an nvlist, the caller is responsible for destroying the returned nvlist with nvlist_destroy(). When the value is a descriptor, the caller is responsible for closing the returned descriptor with close(2). SEE ALSO close(2), free(3), nv(9) HISTORY The dnv API appeared in FreeBSD 11.0. AUTHORS The dnv API was implemented by Pawel Jakub Dawidek <pawel@dawidek.net> under sponsorship from the FreeBSD Foundation. This manual page was written by Adam Starak <starak.adam@gmail.com> FreeBSD 14.0-RELEASE-p11 July 26, 2016 FreeBSD 14.0-RELEASE-p11