X-Git-Url: https://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?a=blobdiff_plain;f=man%2Fsd_journal_print.xml;h=055094c9a2d8070ba2d6e69195e644e45fc1ea62;hb=9a4b012e43f23516373bf398dd9a458439d19939;hp=7eac6c8192567749af637c1d8b5cd3aaedc24daf;hpb=18c7ed186be28800a2eeb37ad31c9c44480d3d9c;p=elogind.git
diff --git a/man/sd_journal_print.xml b/man/sd_journal_print.xml
index 7eac6c819..055094c9a 100644
--- a/man/sd_journal_print.xml
+++ b/man/sd_journal_print.xml
@@ -59,20 +59,20 @@
int sd_journal_print
int priority
- const char* format
+ const char *format
...
int sd_journal_printv
int priority
- const char* format
+ const char *format
va_list ap
int sd_journal_send
- const char* format
+ const char *format
...
@@ -84,7 +84,7 @@
int sd_journal_perror
- const char* message
+ const char *message
@@ -98,20 +98,20 @@
system journal. The first argument is a priority
value. This is followed by a format string and its
parameters, similar to
- printf3
+ printf3
or
- syslog3. The
+ syslog3. The
priority value is one of
- LOG_EMERG,
- LOG_ALERT,
- LOG_CRIT,
- LOG_ERR,
- LOG_WARNING,
- LOG_NOTICE,
- LOG_INFO,
- LOG_DEBUG, as defined in
+ LOG_EMERG,
+ LOG_ALERT,
+ LOG_CRIT,
+ LOG_ERR,
+ LOG_WARNING,
+ LOG_NOTICE,
+ LOG_INFO,
+ LOG_DEBUG, as defined in
syslog.h, see
- syslog3
+ syslog3
for details. It is recommended to use this call to
submit log messages in the application locale or system
locale and in UTF-8 format, but no such restrictions
@@ -120,39 +120,41 @@
sd_journal_printv() is
similar to sd_journal_print() but
takes a variable argument list encapsulated in an
- object of type va_list (see
+ object of type va_list (see
stdarg3
for more information) instead of the format string. It
- is otherwise equivalent in behaviour.
+ is otherwise equivalent in behavior.
sd_journal_send() may be
used to submit structured log entries to the system
journal. It takes a series of format strings, each
immediately followed by their associated parameters,
- terminated by NULL. The strings passed should be of
+ terminated by NULL. The strings passed should be of
the format VARIABLE=value. The
- variable name must be in uppercase and consist only
- of characters, numbers and underscores, and may not
- begin with an underscore. The value can be of any size
- and format. It is highly recommended to submit
- text strings formatted in the UTF-8 character encoding
- only, and submit binary fields only when formatting in
- UTf-8 strings is not sensible. A number of well known
- fields are defined, see
+ variable name must be in uppercase and consist only of
+ characters, numbers and underscores, and may not begin
+ with an underscore. (All assignments that do not
+ follow this syntax will be ignored.) The value can be
+ of any size and format. It is highly recommended to
+ submit text strings formatted in the UTF-8 character
+ encoding only, and submit binary fields only when
+ formatting in UTF-8 strings is not sensible. A number
+ of well known fields are defined, see
systemd.journal-fields7
for details, but additional application defined fields
- may be used.
+ may be used. A variable may be assigned more than one
+ value per entry.
sd_journal_sendv() is
similar to sd_journal_send() but
- takes an array of struct iovec (as
+ takes an array of struct iovec (as
defined in uio.h, see
readv3
for details) instead of the format string. Each
structure should reference one field of the entry to
submit. The second argument specifies the number of
- structures in the
- array. sd_journal_sendv() is
+ structures in the array.
+ sd_journal_sendv() is
particularly useful to submit binary objects to the
journal where that is necessary.
@@ -163,13 +165,13 @@
the passed string, suffixed with ": " and a human
readable representation of the current error code
stored in
- errno3. If
- the message string is passed as NULL or empty string
+ errno3. If
+ the message string is passed as NULL or empty string,
only the error string representation will be written,
prefixed with nothing. An additional journal field
ERRNO= is included in the entry containing the numeric
error code formatted as decimal string. The log
- priority used is LOG_ERR (3).
+ priority used is LOG_ERR (3).
Note that sd_journal_send()
is a wrapper around
@@ -187,12 +189,12 @@ sd_journal_send("MESSAGE=Hello World, this is PID %lu!", (unsigned long) getpid(
Note that these calls implicitly add fields for
the source file, function name and code line where
invoked. This is implemented with macros. If this is
- not desired it can be turned off by defining
+ not desired, it can be turned off by defining
SD_JOURNAL_SUPPRESS_LOCATION before including
sd-journal.h.
- syslog3
- and and sd_journal_print() may
+ syslog3
+ and sd_journal_print() may
largely be used interchangeably
functionality-wise. However, note that log messages
logged via the former take a different path to the
@@ -200,8 +202,8 @@ sd_journal_send("MESSAGE=Hello World, this is PID %lu!", (unsigned long) getpid(
chronological ordering between the two streams cannot
be guaranteed. Using
sd_journal_print() has the
- benefit of logging source code line, file names, and
- functions as meta data along all entries, and
+ benefit of logging source code line, filenames, and
+ functions as metadata along all entries, and
guaranteeing chronological ordering with structured
log entries that are generated via
sd_journal_send(). Using
@@ -214,8 +216,26 @@ sd_journal_send("MESSAGE=Hello World, this is PID %lu!", (unsigned long) getpid(
The four calls return 0 on success or a negative
errno-style error code. The
- errno3
+ errno3
variable itself is not altered.
+
+ If
+ systemd-journald8
+ is not running (the socket is not present), those
+ functions do nothing, and also return 0.
+
+
+
+ Async signal safety
+ sd_journal_sendv() is "async signal
+ safe" in the meaning of signal7.
+
+
+ sd_journal_print,
+ sd_journal_printv,
+ sd_journal_send, and
+ sd_journal_perror are
+ not async signal safe.
@@ -225,10 +245,9 @@ sd_journal_send("MESSAGE=Hello World, this is PID %lu!", (unsigned long) getpid(
sd_journal_printv(),
sd_journal_send() and
sd_journal_sendv() interfaces
- are available as shared library, which can be compiled
+ are available as a shared library, which can be compiled
and linked to with the
- libsystemd-journal
- pkg-config1
+ libsystemd pkg-config1
file.
@@ -239,10 +258,12 @@ sd_journal_send("MESSAGE=Hello World, this is PID %lu!", (unsigned long) getpid(
systemd1,
sd-journal3,
sd_journal_stream_fd3,
- syslog3,
+ syslog3,
perror3,
- errno3,
- systemd.journal-fields7
+ errno3,
+ systemd.journal-fields7,
+ signal7,
+ socket7