union type:</para>
<programlisting>typedef union sd_id128 {
- uint8_t bytes[16];
- uint64_t qwords[2];
+ uint8_t bytes[16];
+ uint64_t qwords[2];
} sd_id128_t;</programlisting>
<para>This union type allows accessing the 128-bit ID as 16
#define SD_MESSAGE_COREDUMP_STR SD_ID128_MAKE_STR(fc,2e,22,bc,6e,e6,47,b6,b9,07,29,ab,34,a2,50,b1)
int main(int argc, char **argv) {
- puts("Match for coredumps: MESSAGE_ID=" SD_MESSAGE_COREDUMP_STR);
+ puts("Match for coredumps: MESSAGE_ID=" SD_MESSAGE_COREDUMP_STR);
}
</programlisting>
following example code will output the string
"fc2e22bc6ee647b6b90729ab34a250b1":</para>
<programlisting>int main(int argc, char *argv[]) {
- puts("Match for coredumps: %s", SD_ID128_CONST_STR(SD_MESSAGE_COREDUMP));
+ puts("Match for coredumps: %s", SD_ID128_CONST_STR(SD_MESSAGE_COREDUMP));
}</programlisting>
<para><constant>SD_ID128_FORMAT_STR</constant> and <function>SD_ID128_FORMAT_VAL()</function> may
format string, as shown in the following example:</para>
<programlisting>int main(int argc, char *argv[]) {
- sd_id128_t id;
- id = SD_ID128_MAKE(ee,89,be,71,bd,6e,43,d6,91,e6,c5,5d,eb,03,02,07);
- printf("The ID encoded in this C file is " SD_ID128_FORMAT_STR ".\n", SD_ID128_FORMAT_VAL(id));
- return 0;
+ sd_id128_t id;
+ id = SD_ID128_MAKE(ee,89,be,71,bd,6e,43,d6,91,e6,c5,5d,eb,03,02,07);
+ printf("The ID encoded in this C file is " SD_ID128_FORMAT_STR ".\n", SD_ID128_FORMAT_VAL(id));
+ return 0;
}</programlisting>
<para><constant>SD_ID128_UUID_FORMAT_STR</constant> is similar to
<para>Use <function>sd_id128_equal()</function> to compare two 128-bit IDs:</para>
<programlisting>int main(int argc, char *argv[]) {
- sd_id128_t a, b, c;
- a = SD_ID128_MAKE(ee,89,be,71,bd,6e,43,d6,91,e6,c5,5d,eb,03,02,07);
- b = SD_ID128_MAKE(f2,28,88,9c,5f,09,44,15,9d,d7,04,77,58,cb,e7,3e);
- c = a;
- assert(sd_id128_equal(a, c));
- assert(!sd_id128_equal(a, b));
- return 0;
+ sd_id128_t a, b, c;
+ a = SD_ID128_MAKE(ee,89,be,71,bd,6e,43,d6,91,e6,c5,5d,eb,03,02,07);
+ b = SD_ID128_MAKE(f2,28,88,9c,5f,09,44,15,9d,d7,04,77,58,cb,e7,3e);
+ c = a;
+ assert(sd_id128_equal(a, c));
+ assert(!sd_id128_equal(a, b));
+ return 0;
}</programlisting>
<para>Use <function>sd_id128_is_null()</function> to check if an 128bit ID consists of only
<constant>NUL</constant> bytes:</para>
<programlisting>int main(int argc, char *argv[]) {
- assert(sd_id128_is_null(SD_ID128_NULL));
+ assert(sd_id128_is_null(SD_ID128_NULL));
}</programlisting>
<para>Note that new, randomized IDs may be generated with