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.\" Common Development and Distribution License ("CDDL"), version 1.0.
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.\" 1.0 of the CDDL.
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.\" Copyright 2015 Joyent, Inc.
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.Dd May 11, 2016
.Dt LCTLFD 3PROC
.Os
.Sh NAME
.Nm Lctlfd
.Nd obtain the thread control file descriptor
.Sh SYNOPSIS
.Lb libproc
.In libproc.h
.Ft int
.Fo Lctlfd
.Fa "struct ps_lwphandle *L"
.Fc
.Sh DESCRIPTION
The
.Fn Lctlfd
function returns a file descriptor to the underlying /proc file system
.Sy ctl
file for the thread identified by the handle
.Fa L .
This may be used for injecting control operations manually; however,
many interfaces for using it are provided by
.Xr libproc 3LIB
itself.
.Pp
The file descriptor is invalidated when the thread handle is released
through
.Xr Lfree 3PROC .
The caller
.Em must not
call
.Xr close 2
on the returned file descriptor.
.Sh INTERFACE STABILITY
.Sy Uncommitted
.Sh MT-LEVEL
See
.Sy LOCKING
in
.Xr libproc 3LIB .
.Sh SEE ALSO
.Xr libproc 3LIB ,
.Xr Lfree 3PROC ,
.Xr Lgrab 3PROC ,
.Xr proc 5