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1.\" $OpenBSD: fuse_session_loop.3,v 1.1 2026/02/01 20:02:58 helg Exp $
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3.\" Copyright (c) 2026 Helg Bredow <helg@openbsd.org>
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17.Dd $Mdocdate: February 1 2026 $
18.Dt FUSE_SESSION_LOOP 3
19.Os
20.Sh NAME
21.Nm fuse_session_loop ,
22.Nm fuse_session_process ,
23.Nm fuse_session_add_chan ,
24.Nm fuse_session_remove_chan ,
25.Nm fuse_session_exit ,
26.Nm fuse_session_exited ,
27.Nm fuse_session_reset
28.Nd manage lifecycle and event handling for a FUSE session
29.Sh SYNOPSIS
30.Lb fuse
31.In fuse_lowlevel.h
32.Ft int
33.Fn fuse_session_loop "struct fuse_session *se"
34.Ft void
35.Fo fuse_session_process
36.Fa "struct fuse_session *se"
37.Fa "struct fuse_chan *ch"
38.Fa "const struct fuse_buf *buf"
39.Fa "struct fuse_buf *outbuf"
40.Fc
41.Ft void
42.Fo fuse_session_add_chan
43.Fa "struct fuse_session *se"
44.Fa "struct fuse_chan *ch"
45.Fc
46.Ft void
47.Fn fuse_session_remove_chan "struct fuse_chan *ch"
48.Ft void
49.Fn fuse_session_exit "struct fuse_session *se"
50.Ft int
51.Fn fuse_session_exited "struct fuse_session *se"
52.Ft void
53.Fn fuse_session_reset "struct fuse_session *se"
54.Sh DESCRIPTION
55These functions are part of the FUSE low-level API and are used to manage the
56lifecycle, communication channel, and event processing of a FUSE session.
57.Pp
58A fuse_session is created with
59.Xr fuse_lowlevel_new 3 .
60.Bl -tag -width Ds
61.It Fn fuse_session_loop "se"
62Run the main event loop for the session
63.Fa se .
64This function blocks and processes incoming requests until
65.Fn fuse_session_exit
66is called.
67.It Fn fuse_session_process "se" "buf" "bufsize" "ch"
68Process a single buffer
69.Fa buf
70received from channel
71.Fa ch
72in the session
73.Fa se .
74If ch is
75.Dv NULL
76then the channel added to the session is used instead.
77Used for manual request handling outside of the main loop.
78.It Fn fuse_session_add_chan "se" "ch"
79Add the communication channel
80.Fa ch
81to the session
82.Fa se .
83Channels are used to receive requests from the kernel.
84A session may be associated with only one channel at a time, and a channel
85may be associated with only one session at a time.
86.It Fn fuse_session_remove_chan "ch"
87Remove the channel
88.Fa ch
89from its associated session.
90.It Fn fuse_session_exit "se"
91Signal the session
92.Fa se
93to exit its event loop.
94This does not destroy the session or unmount the filesystem.
95.It Fn fuse_session_reset "se"
96Reset the session
97.Fa se
98to a non-exited state, allowing the loop to be restarted.
99.El
100.Sh RETURN VALUES
101.Fn fuse_session_loop
102returns 0 on success or -1 on failure.
103.Pp
104.Fn fuse_session_exited
105Returns non-zero if
106.Fn fuse_session_exit
107has been called and the session
108.Fa se
109is marked for termination.
110.Sh SEE ALSO
111.Xr fuse_chan_fd 3 ,
112.Xr fuse_lowlevel_new 3 ,
113.Xr fuse_mount 3
114.Sh STANDARDS
115These library functions conform to FUSE 2.6.
116.Sh HISTORY
117These functions have been available since
118.Ox 7.9 .
119.Sh AUTHORS
120.An Helg Bredow Aq Mt helg@openbsd.org