SD_ID128_TO_STRING(3)sd_id128_to_stringSD_ID128_TO_STRING(3)NAME
sd_id128_to_string, sd_id128_from_string - Format or parse 128-bit IDs
as strings
SYNOPSIS
#include <systemd/sd-id128.h>
char* sd_id128_to_string(sd_id128_t id, char s[33]);
int sd_id128_from_string(const char* s, sd_id128_t* ret);
DESCRIPTIONsd_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 NUL byte.
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.
For more information about the "sd_id128_t" type see sd-id128(3). 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 printf(3). This is easily done using the
SD_ID128_FORMAT_STR and SD_ID128_FORMAT_VAL() macros. For more
information see sd-id128(3).
RETURN VALUEsd_id128_to_string() always succeeds and returns a pointer to the
string array passed in. sd_id128_from_string returns 0 on success, in
which case ret is filled in, or a negative errno-style error code.
NOTES
The sd_id128_to_string() and sd_id128_from_string() interfaces are
available as a shared library, which can be compiled and linked to with
the "libsystemd-id128" pkg-config(1) file.
SEE ALSOsystemd(1), sd-id128(3), printf(3)systemd 208SD_ID128_TO_STRING(3)
