MEMCACHED_TOUCH(3) libmemcached-awesome MEMCACHED_TOUCH(3) NAME memcached_touch - libmemcached Documentation SYNOPSIS #include Compile and link with -lmemcached memcached_return_t <#_CPPv418memcached_return_t> memcached_touch(memcached_st <#_CPPv412memcached_st> *ptr, const char *key, size_t key_length, time_t expiration) Parameters o ptr -- pointer to initialized memcached_st <# _CPPv412memcached_st> struct o key -- the key to touch o key_length -- the length of key without any terminating zero o expiration -- new expiration as a unix timestamp or as relative expiration time in seconds Returns memcached_return_t <#_CPPv418memcached_return_t> indicating success memcached_return_t <#_CPPv418memcached_return_t> memcached_touch_by_key(memcached_st <#_CPPv412memcached_st> *ptr, const char *group_key, size_t group_key_length, const char *key, size_t key_length, time_t expiration) Parameters o ptr -- pointer to initialized memcached_st <# _CPPv412memcached_st> struct o group_key -- the key namespace o group_key_length -- the length of group_key without any terminating zero o key -- the key to touch o key_length -- the length of key without any terminating zero o expiration -- new expiration as a unix timestamp or as relative expiration time in seconds Returns memcached_return_t <#_CPPv418memcached_return_t> indicating success DESCRIPTION memcached_touch() is used to update the expiration time on an existing key. memcached_touch_by_key() works the same, but it takes a master key to find the given value. RETURN VALUE A value of type memcached_return_t <#_CPPv418memcached_return_t> is returned. On success that value will be MEMCACHED_SUCCESS <# _CPPv4N18memcached_return_t17MEMCACHED_SUCCESSE>. Use memcached_strerror() <# _CPPv418memcached_strerrorP12memcached_st18memcached_return_t> to translate this value to a printable string. SEE ALSO memcached(1) libmemcached(3) memcached_strerror(3) 1.1 March 7, 2026 MEMCACHED_TOUCH(3)