sd_id128_to_string, sd_id128_from_string — Format or parse 128-bit IDs as strings
|sd_id128_t id, char s|
|const char *s, sd_id128_t *ret|
sd_id128_to_string() formats a 128-bit
ID as a character string. It expects the ID and a string array
capable of storing 33 characters. The ID will be formatted as 32
lowercase hexadecimal digits and be terminated by a
sd_id128_from_string() implements the reverse operation: it takes a 33 character string
with 32 hexadecimal digits (either lowercase or uppercase, terminated by
NUL) and parses them
back into a 128-bit ID returned in
ret. Alternatively, this call can also parse a
37-character string with a 128-bit ID formatted as RFC UUID. If
ret is passed as NULL the
function will validate the passed ID string, but not actually return it in parsed form.
For more information about the "
Note that these calls operate the same way on all architectures,
i.e. the results do not depend on endianness.
When formatting a 128-bit ID into a string, it is often
easier to use a format string for
This is easily done using the
SD_ID128_FORMAT_VAL() macros. For more
sd_id128_to_string() always succeeds
and returns a pointer to the string array passed in.
sd_id128_from_string returns 0 on success, in
ret is filled in, or a negative
errno-style error code.
These APIs are implemented as a shared
library, which can be compiled and linked to with the