LLAPI_HSM_STATE_SET(3)

✨ LLAPI_HSM_STATE_SET(3) ✨

okay bestie, sit down, hydrate, and let me tell you about a lil function from the Lustre Library Functions collection 💖 it's called llapi_hsm_state_set, and it's literally the girlboss that sets your HSM flags for you. no cap.

---

🌸 NAME 🌸

llapi_hsm_state_set, llapi_hsm_state_set_fd — set HSM flags for a file on a Lustre filesystem 🦋

---

👑 SYNOPSIS 👑

#include <lustre/lustreapi.h>

int llapi_hsm_state_set(const char *path, __u64 setmask,
                        __u64 clearmask, __u32 archive_id);

int llapi_hsm_state_set_fd(int fd, __u64 setmask,
                           __u64 clearmask, __u32 archive_id);

two flavors, same energy, pick your fave 💅

---

💜 DESCRIPTION 💜

so like, llapi_hsm_state_set() and llapi_hsm_state_set_fd() do the thing where they set, clear HSM flags and modify the archive ID for the file pointed at by path or fd. it's giving glow-up, but for metadata 🌈

• setmask — the mask of flags you wanna add. yes queen, stack them on 💖
• clearmask — the mask of flags you wanna remove. bye bestie, not your era anymore 💀
• archive_id — the archive ID (has to be greater than 0) used for this file. use 0 if you do not want to change it. iconic "leave it alone" behaviour fr fr 🎀

head over to llapi_hsm_state_get(3) if you wanna see which flags are actually available, iykyk 👀

---

🫶 RETURN VALUES 🫶

llapi_hsm_state_set() and llapi_hsm_state_set_fd() return:

• 0 — on success 🎉 slay
• != 0 — on failure, and errno is set appropriately (as it should be, she's communicative) 😭

---

💀 ERRORS 💀

okay so when things go sideways, you might catch one of these:

• -ENOMEM — failed to allocate memory. lowkey tragic, no memory no party 🙈
• -ENAMETOOLONG — path was too long. that path was yapping too much 💅
• -ENOENT — path does not point to a file or a directory. she's not there bestie, she left 👑
• -ENOTTY — path does not point to a Lustre filesystem. wrong universe, girl 🌸
• -EINVAL — the provided masks resulted in an incompatible set of flags. the vibes did not pass the vibe check 💔

---

🔥 EXAMPLES 🔥

here's a whole main character moment in C, showing you exactly how it's done:

#include <stdlib.h>
#include <stdio.h>
#include <errno.h>

#include <lustre/lustreapi.h>

int main(int argc, char **argv)
{
     int rc;

     if (argc < 2) {
          fprintf(stderr, "usage: prog FILEPATH\n");
          exit(1);
     }

     rc = llapi_hsm_state_set(argv[1], HS_DIRTY|HS_NORELEASE, 0, 0);
     if (rc != 0) {
          fprintf(stderr, "Can't change hsm flags for %s: %s\n",
               argv[1], strerror(errno = -rc));
          exit(rc);
     }

     exit(0);
}

notice how the archive_id is 0 there? that's the "don't touch it" energy. periodt 🎀

---

⭐ AVAILABILITY ⭐

llapi_hsm_state_set and llapi_hsm_state_set_fd are part of the lustre(7) user application interface library since release 2.4.0. yes she's been here a while and she's been serving the whole time 💖✨

---

🌈 SEE ALSO 🌈

• llapi_hsm_state_get(3)
• llapi_hsm_state_get_fd(3)
• lustre(7)
• lustreapi(7)

---

bestie reminder: the flags live over in llapi_hsm_state_get(3), so go read that first before you start throwing masks around 🎀

that's the whole page! written by the Lustre User API girlies on 2024-08-27 — stay slaying, stay aligned, and may your errno always be 0 💅💖🦋