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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 | libtraceevent(3) ================ NAME ---- tep_find_common_field, tep_find_field, tep_find_any_field - Search for a field in an event. SYNOPSIS -------- [verse] -- *#include <event-parse.h>* struct tep_format_field pass:[*]*tep_find_common_field*(struct tep_event pass:[*]_event_, const char pass:[*]_name_); struct tep_format_field pass:[*]*tep_find_field*(struct tep_event_ormat pass:[*]_event_, const char pass:[*]_name_); struct tep_format_field pass:[*]*tep_find_any_field*(struct tep_event pass:[*]_event_, const char pass:[*]_name_); -- DESCRIPTION ----------- These functions search for a field with given name in an event. The field returned can be used to find the field content from within a data record. The _tep_find_common_field()_ function searches for a common field with _name_ in the _event_. The _tep_find_field()_ function searches for an event specific field with _name_ in the _event_. The _tep_find_any_field()_ function searches for any field with _name_ in the _event_. RETURN VALUE ------------ The _tep_find_common_field(), _tep_find_field()_ and _tep_find_any_field()_ functions return a pointer to the found field, or NULL in case there is no field with the requested name. EXAMPLE ------- [source,c] -- #include <event-parse.h> ... void get_htimer_info(struct tep_handle *tep, struct tep_record *record) { struct tep_format_field *field; struct tep_event *event; long long softexpires; int mode; int pid; event = tep_find_event_by_name(tep, "timer", "hrtimer_start"); field = tep_find_common_field(event, "common_pid"); if (field == NULL) { /* Cannot find "common_pid" field in the event */ } else { /* Get pid from the data record */ pid = tep_read_number(tep, record->data + field->offset, field->size); } field = tep_find_field(event, "softexpires"); if (field == NULL) { /* Cannot find "softexpires" event specific field in the event */ } else { /* Get softexpires parameter from the data record */ softexpires = tep_read_number(tep, record->data + field->offset, field->size); } field = tep_find_any_field(event, "mode"); if (field == NULL) { /* Cannot find "mode" field in the event */ } else { /* Get mode parameter from the data record */ mode = tep_read_number(tep, record->data + field->offset, field->size); } } ... -- 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 |