.\" $OpenBSD: fuse_session_loop.3,v 1.1 2026/02/01 20:02:58 helg Exp $
.\"
.\" Copyright (c) 2026 Helg Bredow <helg@openbsd.org>
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.Dd $Mdocdate: February 1 2026 $
.Dt FUSE_SESSION_LOOP 3
.Os
.Sh NAME
.Nm fuse_session_loop ,
.Nm fuse_session_process ,
.Nm fuse_session_add_chan ,
.Nm fuse_session_remove_chan ,
.Nm fuse_session_exit ,
.Nm fuse_session_exited ,
.Nm fuse_session_reset
.Nd manage lifecycle and event handling for a FUSE session
.Sh SYNOPSIS
.Lb fuse
.In fuse_lowlevel.h
.Ft int
.Fn fuse_session_loop "struct fuse_session *se"
.Ft void
.Fo fuse_session_process
.Fa "struct fuse_session *se"
.Fa "struct fuse_chan *ch"
.Fa "const struct fuse_buf *buf"
.Fa "struct fuse_buf *outbuf"
.Fc
.Ft void
.Fo fuse_session_add_chan
.Fa "struct fuse_session *se"
.Fa "struct fuse_chan *ch"
.Fc
.Ft void
.Fn fuse_session_remove_chan "struct fuse_chan *ch"
.Ft void
.Fn fuse_session_exit "struct fuse_session *se"
.Ft int
.Fn fuse_session_exited "struct fuse_session *se"
.Ft void
.Fn fuse_session_reset "struct fuse_session *se"
.Sh DESCRIPTION
These functions are part of the FUSE low-level API and are used to manage the
lifecycle, communication channel, and event processing of a FUSE session.
.Pp
A fuse_session is created with
.Xr fuse_lowlevel_new 3 .
.Bl -tag -width Ds
.It Fn fuse_session_loop "se"
Run the main event loop for the session
.Fa se .
This function blocks and processes incoming requests until
.Fn fuse_session_exit
is called.
.It Fn fuse_session_process "se" "buf" "bufsize" "ch"
Process a single buffer
.Fa buf
received from channel
.Fa ch
in the session
.Fa se .
If ch is
.Dv NULL
then the channel added to the session is used instead.
Used for manual request handling outside of the main loop.
.It Fn fuse_session_add_chan "se" "ch"
Add the communication channel
.Fa ch
to the session
.Fa se .
Channels are used to receive requests from the kernel.
A session may be associated with only one channel at a time, and a channel
may be associated with only one session at a time.
.It Fn fuse_session_remove_chan "ch"
Remove the channel
.Fa ch
from its associated session.
.It Fn fuse_session_exit "se"
Signal the session
.Fa se
to exit its event loop.
This does not destroy the session or unmount the filesystem.
.It Fn fuse_session_reset "se"
Reset the session
.Fa se
to a non-exited state, allowing the loop to be restarted.
.El
.Sh RETURN VALUES
.Fn fuse_session_loop
returns 0 on success or -1 on failure.
.Pp
.Fn fuse_session_exited
Returns non-zero if
.Fn fuse_session_exit
has been called and the session
.Fa se
is marked for termination.
.Sh SEE ALSO
.Xr fuse_chan_fd 3 ,
.Xr fuse_lowlevel_new 3 ,
.Xr fuse_mount 3
.Sh STANDARDS
These library functions conform to FUSE 2.6.
.Sh HISTORY
These functions have been available since
.Ox 7.9 .
.Sh AUTHORS
.An Helg Bredow Aq Mt helg@openbsd.org