LIBTRACEEVENT(3)

💖 NAME 💖

tep_read_number_field — bestie, it reads a number out of raw data. that's it, that's the whole job 💅

so like, this is your girl libtraceevent(3) and she's here to help you pull an actual number out of a pile of raw bytes. iconic behavior tbh.

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✨ SYNOPSIS ✨

#include <event-parse.h>

int tep_read_number_field(struct tep_format_field *field, const void *data, unsigned long long *value);

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🦋 DESCRIPTION 🦋

okay so the way tep_read_number_field() works is: it reads the value of the field straight out of the raw data, and then it stores it in value. no cap.

and here's the cute part — it sets that value according to the endianness of the raw data and the endianness of the current machine, then stores it in value. so it's giving endianness-aware, it's giving portability, it's literally doing the byte math so you don't have to 🙈✨

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🎀 RETURN VALUE 🎀

• 0 — slay, success, we ate 🍓
• -1 — uh oh, an error happened 😭

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🌸 EXAMPLE 🌸

#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 */
        }
}
...

see how she grabbed the common_pid field and just… pulled the number right out of record->data? main character energy fr fr 👑

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🧚 FILES 🧚

• event-parse.h — the header file you gotta include so you can have access to the library APIs. yes bestie, you need it, don't skip it 💜
• -ltraceevent — the linker switch you add when building a program that uses the library. it's giving "don't forget to link me" 🌈

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💫 SEE ALSO 💫

libtraceevent(3), trace-cmd(1)

go read those too, iykyk 🫶

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👑 AUTHOR 👑

• Steven Rostedt <rostedt@goodmis.org[1]>, author of libtraceevent.
• Tzvetomir Stoyanov <tz.stoyanov@gmail.com[2]>, author of this man page.

(the legends themselves, no big deal 💅)

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😭 REPORTING BUGS 😭

found something cursed? report bugs to <linux-trace-devel@vger.kernel.org[3]> — they wanna know, fr fr 💀

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💖 LICENSE 💖

libtraceevent is Free Software licensed under the GNU LGPL 2.1. free as in freedom, bestie 🦋

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⭐ RESOURCES ⭐

https://git.kernel.org/pub/scm/libs/libtrace/libtraceevent.git/

(the sacred texts 📜✨)

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🎀 NOTES 🎀

1. rostedt@goodmis.org mailto:rostedt@goodmis.org
2. tz.stoyanov@gmail.com mailto:tz.stoyanov@gmail.com
3. linux-trace-devel@vger.kernel.org mailto:linux-trace-devel@vger.kernel.org

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and that's the whole page, bestie 💖 this was libtraceevent 1.9.0, dated 06/15/2026, and it lives in section LIBTRACEEVENT(3) of the manual. periodt. 💅🌸