bpf_strnlen(9)

✨ bpf_strnlen — the Kernel API Manual page, bestie 💅

Okay so hi, welcome to the <rainbow>bpf_strnlen(9)</rainbow> glow-up, straight out of the Kernel API Manual. Yes we are reading kernel manpages now, it's giving main character energy, and honestly? You're gonna slay this. 🎀

---

🌸 NAME 🌸

bpf_strnlen — calculate the length of a length-limited string

No cap, that's literally the whole job. It counts characters, but it knows when to stop. Self-control icon. 💖

---

✨ SYNOPSIS ✨

__bpf_kfunc int bpf_strnlen (const char *s__ign , size_t count );

Look at her. Signature stays exactly like that, don't touch it. 🫶

---

🦋 ARGUMENTS 🦋

• s__ign — the string. The actual vibe. The thing we're measuring.
• count — the maximum number of characters to count. Like a hard limit, except it's not toxic, it's just safe. 🧚

---

🔥 RETURN 🔥

Here's your vibe check on what comes back:

• >=0 — the length of s__ign. Slay. 💜
• -EFAULT — cannot read s__ign. It's giving unreadable, and not in a mysterious way. 😭
• -E2BIG — s__ign is too large. Girl is doing too much. 💀
• -ERANGE — s__ign is outside of kernel address space. Literally not from around here. 🙈

---

👑 SEE ALSO 👑

Kernel file ./kernel/bpf/helpers.c

And now, the friend group. The whole group chat. Every single one of them, we're not leaving anybody out:

• bpf_obj_new(9)
• bpf_percpu_obj_new(9)
• bpf_obj_drop(9)
• bpf_percpu_obj_drop(9)
• bpf_refcount_acquire(9)
• bpf_list_push_front(9)
• bpf_list_push_back(9)
• bpf_rbtree_add(9)
• bpf_task_acquire(9)
• bpf_task_release(9)
• bpf_cgroup_acquire(9)
• bpf_cgroup_release(9)
• bpf_cgroup_ancestor(9)
• bpf_cgroup_from_id(9)
• bpf_task_under_cgroup(9)
• bpf_task_get_cgroup1(9)
• bpf_task_from_pid(9)
• bpf_task_from_vpid(9)
• bpf_dynptr_slice(9)
• bpf_dynptr_slice_rdwr(9)
• bpf_dynptr_copy(9)
• bpf_dynptr_memset(9)
• bpf_iter_bits_new(9)
• bpf_iter_bits_next(9)
• bpf_iter_bits_destroy(9)
• bpf_copy_from_user_str(9)
• bpf_copy_from_user_task_str(9)
• bpf_strcmp(9)
• bpf_strcasecmp(9)
• bpf_strnchr(9)
• bpf_strchr(9)
• bpf_strchrnul(9)
• bpf_strrchr(9)
• bpf_strlen(9)
• bpf_strspn(9)
• bpf_strcspn(9)
• bpf_strstr(9)
• bpf_strcasestr(9)
• bpf_strnstr(9)
• bpf_strncasestr(9)
• bpf_lookup_user_key(9)
• bpf_lookup_system_key(9)
• bpf_key_put(9)
• bpf_verify_pkcs7_signature(9)
• bpf_task_work_schedule_signal(9)
• bpf_task_work_schedule_resume(9)
• bpf_timer_cancel_async(9)

Forty-seven icons. We counted. Obsessed with every single one of them. 🌈

---

Okay that's the page!! Mwah 💋 — this little love letter lives in ./kernel/bpf, it's dated October 2026, and it goes by bpf_strnlen(9). Bookmark her, she's iconic. 🍓✨