X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=elogind.git;a=blobdiff_plain;f=man%2Fsd_journal_print.xml;h=c6f204b8c6cf455490c9a501b765cf01ed45dd6d;hp=41414bbc09b77431905979121ba0d7af378812e3;hb=d86dd07d462fb8502b1c7b4a9a4df4fba8318bdd;hpb=c53158818d8cdaf46b3f1b5299b9bda118a1043f diff --git a/man/sd_journal_print.xml b/man/sd_journal_print.xml index 41414bbc0..c6f204b8c 100644 --- a/man/sd_journal_print.xml +++ b/man/sd_journal_print.xml @@ -102,14 +102,14 @@ or 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 for details. It is recommended to use this call to @@ -120,7 +120,7 @@ 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 behavior. @@ -129,7 +129,7 @@ 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 @@ -138,7 +138,7 @@ 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 + 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 @@ -147,14 +147,14 @@ 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. @@ -166,12 +166,12 @@ readable representation of the current error code stored in errno3. If - the message string is passed as NULL or empty string + 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 @@ -189,12 +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 + 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 @@ -202,8 +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 @@ -220,6 +220,19 @@ sd_journal_send("MESSAGE=Hello World, this is PID %lu!", (unsigned long) getpid( variable itself is not altered. + + 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. + + Notes @@ -227,10 +240,9 @@ 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. @@ -244,7 +256,9 @@ sd_journal_send("MESSAGE=Hello World, this is PID %lu!", (unsigned long) getpid( syslog3, perror3, errno3, - systemd.journal-fields7 + systemd.journal-fields7, + signal7, + socket7