fcntl_setdeleg(9)

🎀 NAME 🎀

okay so welcome to the fcntl_setdeleg(9) page from the Kernel API Manual, bestie 💖 — this one is all about fcntl_setdeleg, and what it does is sets a delegation on an open file. slay.

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✨ SYNOPSIS ✨

the whole signature is giving:

int fcntl_setdeleg (unsigned int fd , struct file *filp , struct
delegation *deleg );

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🦋 ARGUMENTS 🦋

• fd — the open file descriptor, aka the little number bestie uses to point at the file 👑
• filp — the file pointer, literally the struct file * in the chat 🌸
• deleg — the delegation request from userland, coming in hot from userspace 💅

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💜 DESCRIPTION 💜

Call this fcntl to establish a delegation on the file. no cap, that's the whole main-character move ✨

okay but important, bestie 🫶 — you also need to call F_SETSIG to receive a signal when the lease is broken. don't skip that part, iykyk 😭

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🌈 SEE ALSO 🌈

Kernel file ./fs/locks.c — literally the lock girlie cinematic universe 💀:

• locks_owner_has_blockers(9)
• lease_open_conflict(9)
• locks_delete_block(9)
• posix_lock_file(9)
• posix_lock_inode_wait(9)
• inode_lease_ignore_mask(9)
• __break_lease(9)
• lease_get_mtime(9)
• __fcntl_getlease(9)
• generic_setlease(9)
• vfs_setlease(9)
• fcntl_setlease(9)
• flock_lock_inode_wait(9)
• locks_lock_inode_wait(9)
• sys_flock(9)
• vfs_test_lock(9)
• locks_translate_pid(9)
• vfs_lock_file(9)
• vfs_cancel_lock(9)
• vfs_inode_has_locks(9)

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mwah 💋 — source/version: ./fs; date: October 2026. periodt 🫶✨