vfs_setpos(9)

💅 NAME 💅

vfs_setpos — update the file offset for lseek

Okay so bestie, welcome to vfs_setpos(9) from the Kernel API Manual. This is the helper that updates the file offset for lseek, and it's lowkey iconic. ✨

✨ SYNOPSIS ✨

loff_t vfs_setpos (struct file *file , loff_t offset , loff_t maxsize );

🫶 ARGUMENTS 🫶

• file — file structure in question (the main character, obviously 💅)
• offset — file offset to seek to
• maxsize — maximum file size

🌸 DESCRIPTION 🌸

This is a low-level filesystem helper for updating the file offset to the value specified by offset — but only if the given offset is valid and it is not equal to the current file offset. No cap, that's the condition. 🫶

On success, it returns the specified offset. On an invalid offset, it returns -EINVAL. That's the vibe check, and invalid offsets do not pass. 💀✨

It's giving "low-level filesystem helper," so don't expect it to do extra side quests. It does its one job and slays. 😭

🔥 SEE ALSO 🔥

Kernel file ./fs/read_write.c:

• vfs_setpos_cookie(9)
• must_set_pos(9)
• generic_file_llseek_size(9)
• generic_llseek_cookie(9)
• generic_file_llseek(9)
• fixed_size_llseek(9)
• no_seek_end_llseek(9)
• no_seek_end_llseek_size(9)
• noop_llseek(9)

Mwah 💋 — this page is sourced from ./fs, version/date stamped October 2026, and it's vfs_setpos(9). Periodt. 🎀