'\" t
.\"     Title: sys_flock
.\"    Author: [FIXME: author] [see http://docbook.sf.net/el/author]
.\" Generator: DocBook XSL Stylesheets v1.78.1 <http://docbook.sf.net/>
.\"      Date: January 2017
.\"    Manual: The Linux VFS
.\"    Source: Kernel Hackers Manual 4.8.15
.\"  Language: English
.\"
.TH "SYS_FLOCK" "9" "January 2017" "Kernel Hackers Manual 4\&.8\&." "The Linux VFS"
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.SH "NAME"
sys_flock \- \fBflock\fR system call\&.
.SH "SYNOPSIS"
.HP \w'long\ sys_flock('u
.BI "long sys_flock(unsigned\ int\ " "fd" ", unsigned\ int\ " "cmd" ");"
.SH "ARGUMENTS"
.PP
\fIfd\fR
.RS 4
the file descriptor to lock\&.
.RE
.PP
\fIcmd\fR
.RS 4
the type of lock to apply\&.
.RE
.SH "DESCRIPTION"
.PP
Apply a
\fBFL_FLOCK\fR
style lock to an open file descriptor\&. The
\fIcmd\fR
can be one of
.PP
\fBLOCK_SH\fR
\-\- a shared lock\&.
.PP
\fBLOCK_EX\fR
\-\- an exclusive lock\&.
.PP
\fBLOCK_UN\fR
\-\- remove an existing lock\&.
.PP
\fBLOCK_MAND\fR
\-\- a `mandatory\*(Aq flock\&. This exists to emulate Windows Share Modes\&.
.PP
\fBLOCK_MAND\fR
can be combined with
\fBLOCK_READ\fR
or
\fBLOCK_WRITE\fR
to allow other processes read and write access respectively\&.
.SH "COPYRIGHT"
.br