diff --git a/Makefile-man.am b/Makefile-man.am
index 5760878fe3..a900b8d25a 100644
--- a/Makefile-man.am
+++ b/Makefile-man.am
@@ -239,6 +239,7 @@ MANPAGES_ALIAS += \
man/SD_ID128_FORMAT_STR.3 \
man/SD_ID128_FORMAT_VAL.3 \
man/SD_ID128_MAKE.3 \
+ man/SD_ID128_NULL.3 \
man/SD_INFO.3 \
man/SD_JOURNAL_APPEND.3 \
man/SD_JOURNAL_CURRENT_USER.3 \
@@ -396,6 +397,7 @@ MANPAGES_ALIAS += \
man/sd_id128_from_string.3 \
man/sd_id128_get_boot.3 \
man/sd_id128_get_invocation.3 \
+ man/sd_id128_is_null.3 \
man/sd_id128_t.3 \
man/sd_is_mq.3 \
man/sd_is_socket.3 \
@@ -590,6 +592,7 @@ man/SD_ID128_CONST_STR.3: man/sd-id128.3
man/SD_ID128_FORMAT_STR.3: man/sd-id128.3
man/SD_ID128_FORMAT_VAL.3: man/sd-id128.3
man/SD_ID128_MAKE.3: man/sd-id128.3
+man/SD_ID128_NULL.3: man/sd-id128.3
man/SD_INFO.3: man/sd-daemon.3
man/SD_JOURNAL_APPEND.3: man/sd_journal_get_fd.3
man/SD_JOURNAL_CURRENT_USER.3: man/sd_journal_open.3
@@ -747,6 +750,7 @@ man/sd_id128_equal.3: man/sd-id128.3
man/sd_id128_from_string.3: man/sd_id128_to_string.3
man/sd_id128_get_boot.3: man/sd_id128_get_machine.3
man/sd_id128_get_invocation.3: man/sd_id128_get_machine.3
+man/sd_id128_is_null.3: man/sd-id128.3
man/sd_id128_t.3: man/sd-id128.3
man/sd_is_mq.3: man/sd_is_fifo.3
man/sd_is_socket.3: man/sd_is_fifo.3
@@ -1053,6 +1057,9 @@ man/SD_ID128_FORMAT_VAL.html: man/sd-id128.html
man/SD_ID128_MAKE.html: man/sd-id128.html
$(html-alias)
+man/SD_ID128_NULL.html: man/sd-id128.html
+ $(html-alias)
+
man/SD_INFO.html: man/sd-daemon.html
$(html-alias)
@@ -1524,6 +1531,9 @@ man/sd_id128_get_boot.html: man/sd_id128_get_machine.html
man/sd_id128_get_invocation.html: man/sd_id128_get_machine.html
$(html-alias)
+man/sd_id128_is_null.html: man/sd-id128.html
+ $(html-alias)
+
man/sd_id128_t.html: man/sd-id128.html
$(html-alias)
diff --git a/man/sd-id128.xml b/man/sd-id128.xml
index ea7972055d..5f24feff8e 100644
--- a/man/sd-id128.xml
+++ b/man/sd-id128.xml
@@ -47,10 +47,12 @@
sd-id128
sd_id128_t
SD_ID128_MAKE
+ SD_ID128_NULL
SD_ID128_CONST_STR
SD_ID128_FORMAT_STR
SD_ID128_FORMAT_VAL
sd_id128_equal
+ sd_id128_is_null
APIs for processing 128-bit IDs
@@ -88,8 +90,8 @@
union type:
typedef union sd_id128 {
- uint8_t bytes[16];
- uint64_t qwords[2];
+ uint8_t bytes[16];
+ uint64_t qwords[2];
} sd_id128_t;
This union type allows accessing the 128-bit ID as 16
@@ -108,37 +110,46 @@
#define SD_MESSAGE_COREDUMP SD_ID128_MAKE(fc,2e,22,bc,6e,e6,47,b6,b9,07,29,ab,34,a2,50,b1)
+ SD_ID128_NULL may be used to refer to the 128bit ID consisting of only NUL
+ bytes.
+
SD_ID128_CONST_STR() may be used to
convert constant 128-bit IDs into constant strings for output. The
following example code will output the string
"fc2e22bc6ee647b6b90729ab34a250b1":
int main(int argc, char *argv[]) {
- puts(SD_ID128_CONST_STR(SD_MESSAGE_COREDUMP));
+ puts(SD_ID128_CONST_STR(SD_MESSAGE_COREDUMP));
}
- SD_ID128_FORMAT_STR and
+ SD_ID128_FORMAT_STR() and
SD_ID128_FORMAT_VAL() may be used to format a
128-bit ID in a
printf3
format string, as shown in the following example:
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;
}
Use sd_id128_equal() to compare two 128-bit IDs:
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;
+}
+
+ Use sd_id128_is_null() to check if an 128bit ID consists of only NUL bytes:
+
+ int main(int argc, char *argv[]) {
+ assert(sd_id128_is_null(SD_ID128_NULL));
}
Note that new, randomized IDs may be generated with