scsw_stctl(9)

💅 scsw_stctl — it's giving "just give me the stctl field" (Kernel API Manual, section 9, bestie)

okay so real talk, this page is a kernel API manual page, like section 9 energy, and the whole entire vibe is: one tiny helper, one big job. let's get into it ✨

---

🌸 NAME 🌸

scsw_stctl — literally just returns the stctl field, that's the whole gig 🎀

---

✨ SYNOPSIS ✨

u32 scsw_stctl (union scsw *scsw );

one function, one pointer, no drama. slay.

---

🫶 ARGUMENTS 🫶

• scsw — pointer to scsw. yep. that's the whole argument list. it's giving minimalism icon behavior 👑

---

💖 DESCRIPTION 💖

okay so here's the tea: scsw_stctl returns the value of the stctl field of the specified scsw, regardless of whether it is a transport mode or command mode scsw.

that's it. that's the function. no cap, it just hands you the stctl value either way. lowkey the most unbothered function in the whole header file and honestly? iconic. 🔥

---

🦋 SEE ALSO 🦋

bestie there is SO much more lore where this came from. the source of truth lives in the kernel file ./arch/s390/include/asm/scsw.h, and the whole friend group is here:

• the structs & the union: struct cmd_scsw(9), struct tm_scsw(9), struct eadm_scsw(9), union scsw(9)
• the field-getter girlies: scsw_is_tm(9), scsw_key(9), scsw_eswf(9), scsw_cc(9), scsw_ectl(9), scsw_pno(9), scsw_fctl(9), scsw_actl(9), scsw_dstat(9), scsw_cstat(9)
• the command-mode validators: scsw_cmd_is_valid_key(9), scsw_cmd_is_valid_sctl(9), scsw_cmd_is_valid_eswf(9), scsw_cmd_is_valid_cc(9), scsw_cmd_is_valid_fmt(9), scsw_cmd_is_valid_pfch(9), scsw_cmd_is_valid_isic(9), scsw_cmd_is_valid_alcc(9), scsw_cmd_is_valid_ssi(9), scsw_cmd_is_valid_zcc(9), scsw_cmd_is_valid_ectl(9), scsw_cmd_is_valid_pno(9), scsw_cmd_is_valid_fctl(9), scsw_cmd_is_valid_actl(9), scsw_cmd_is_valid_stctl(9), scsw_cmd_is_valid_dstat(9), scsw_cmd_is_valid_cstat(9)
• the transport-mode validators: scsw_tm_is_valid_key(9), scsw_tm_is_valid_eswf(9), scsw_tm_is_valid_cc(9), scsw_tm_is_valid_fmt(9), scsw_tm_is_valid_x(9), scsw_tm_is_valid_q(9), scsw_tm_is_valid_ectl(9), scsw_tm_is_valid_pno(9), scsw_tm_is_valid_fctl(9), scsw_tm_is_valid_actl(9), scsw_tm_is_valid_stctl(9), scsw_tm_is_valid_dstat(9), scsw_tm_is_valid_cstat(9), scsw_tm_is_valid_fcxs(9), scsw_tm_is_valid_schxs(9)
• the mode-agnostic validators: scsw_is_valid_actl(9), scsw_is_valid_cc(9), scsw_is_valid_cstat(9), scsw_is_valid_dstat(9), scsw_is_valid_ectl(9), scsw_is_valid_eswf(9), scsw_is_valid_fctl(9), scsw_is_valid_key(9), scsw_is_valid_pno(9), scsw_is_valid_stctl(9)
• the solicited checkers: scsw_cmd_is_solicited(9), scsw_tm_is_solicited(9), scsw_is_solicited(9)

go read them all, i'll wait 💜

---

💀 reminder: this page is from ./arch/s390/include/asm and it's dated October 2026, so if you're reading this in some other timeline, that's a you problem bestie 🧚

---

and that's the whole page!! footer said scsw_stctl(9), path ./arch/s390/include/asm, October 2026 — and honestly it ate. periodt. 💅✨🌸