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| author |   Tzvetomir Stoyanov <tstoyanov@vmware.com> | 2019-05-10 15:56:27 -0400 |
|---|---|---|
| committer |   Arnaldo Carvalho de Melo <acme@redhat.com> | 2019-05-15 16:36:48 -0300 |
| commit | 95ec2822a976af27c9cb77cdc01c650a3640adfa (patch) | |
| tree | 8923cf6001ede1141a865530ac080300cb9d100b /tools/lib/traceevent/Documentation/libtraceevent-field_read.txt | |
| parent | tools lib traceevent: Man pages for print field APIs (diff) | |
| download | linux-dev-95ec2822a976af27c9cb77cdc01c650a3640adfa.tar.xz linux-dev-95ec2822a976af27c9cb77cdc01c650a3640adfa.zip | |
tools lib traceevent: Man page for tep_read_number_field()
Create man page for libtraceevent API tep_read_number_field().
Signed-off-by: Tzvetomir Stoyanov <tstoyanov@vmware.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: linux-trace-devel@vger.kernel.org
Link: http://lore.kernel.org/linux-trace-devel/20190503091119.23399-21-tstoyanov@vmware.com
Link: http://lkml.kernel.org/r/20190510200109.219394901@goodmis.org
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Diffstat (limited to '')
| -rw-r--r-- | tools/lib/traceevent/Documentation/libtraceevent-field_read.txt | 81 |
1 files changed, 81 insertions, 0 deletions
diff --git a/tools/lib/traceevent/Documentation/libtraceevent-field_read.txt b/tools/lib/traceevent/Documentation/libtraceevent-field_read.txt new file mode 100644 index 000000000000..64e9e25d3fd9 --- /dev/null +++ b/tools/lib/traceevent/Documentation/libtraceevent-field_read.txt @@ -0,0 +1,81 @@ +libtraceevent(3) +================ + +NAME +---- +tep_read_number_field - Reads a number from raw data. + +SYNOPSIS +-------- +[verse] +-- +*#include <event-parse.h>* + +int *tep_read_number_field*(struct tep_format_field pass:[*]_field_, const void pass:[*]_data_, unsigned long long pass:[*]_value_); +-- + +DESCRIPTION +----------- +The _tep_read_number_field()_ function reads the value of the _field_ from the +raw _data_ and stores it in the _value_. The function sets the _value_ according +to the endianness of the raw data and the current machine and stores it in +_value_. + +RETURN VALUE +------------ +The _tep_read_number_field()_ function retunrs 0 in case of success, or -1 in +case of an error. + +EXAMPLE +------- +[source,c] +-- +#include <event-parse.h> +... +struct tep_handle *tep = tep_alloc(); +... +struct tep_event *event = tep_find_event_by_name(tep, "timer", "hrtimer_start"); +... +void process_record(struct tep_record *record) +{ + unsigned long long pid; + struct tep_format_field *field_pid = tep_find_common_field(event, "common_pid"); + + if (tep_read_number_field(field_pid, record->data, &pid) != 0) { + /* Failed to get "common_pid" value */ + } +} +... +-- +FILES +----- +[verse] +-- +*event-parse.h* + Header file to include in order to have access to the library APIs. +*-ltraceevent* + Linker switch to add when building a program that uses the library. +-- + +SEE ALSO +-------- +_libtraceevent(3)_, _trace-cmd(1)_ + +AUTHOR +------ +[verse] +-- +*Steven Rostedt* <rostedt@goodmis.org>, author of *libtraceevent*. +*Tzvetomir Stoyanov* <tz.stoyanov@gmail.com>, author of this man page. +-- +REPORTING BUGS +-------------- +Report bugs to <linux-trace-devel@vger.kernel.org> + +LICENSE +------- +libtraceevent is Free Software licensed under the GNU LGPL 2.1 + +RESOURCES +--------- +https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git |