xref: /freebsd/lib/libsys/closefrom.2 (revision 8269e7673cf033aba67dab8264fe719920c70f87)
1*8269e767SBrooks Davis.\" Copyright (c) 2009 Hudson River Trading LLC
2*8269e767SBrooks Davis.\" Written by: John H. Baldwin <jhb@FreeBSD.org>
3*8269e767SBrooks Davis.\" All rights reserved.
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8*8269e767SBrooks Davis.\" 1. Redistributions of source code must retain the above copyright
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26*8269e767SBrooks Davis.Dd March 3, 2022
27*8269e767SBrooks Davis.Dt CLOSEFROM 2
28*8269e767SBrooks Davis.Os
29*8269e767SBrooks Davis.Sh NAME
30*8269e767SBrooks Davis.Nm closefrom ,
31*8269e767SBrooks Davis.Nm close_range
32*8269e767SBrooks Davis.Nd delete open file descriptors
33*8269e767SBrooks Davis.Sh LIBRARY
34*8269e767SBrooks Davis.Lb libc
35*8269e767SBrooks Davis.Sh SYNOPSIS
36*8269e767SBrooks Davis.In unistd.h
37*8269e767SBrooks Davis.Ft void
38*8269e767SBrooks Davis.Fn closefrom "int lowfd"
39*8269e767SBrooks Davis.Ft int
40*8269e767SBrooks Davis.Fn close_range "u_int lowfd" "u_int highfd" "int flags"
41*8269e767SBrooks Davis.Sh DESCRIPTION
42*8269e767SBrooks DavisThe
43*8269e767SBrooks Davis.Fn closefrom
44*8269e767SBrooks Davissystem call deletes all open file descriptors greater than or equal to
45*8269e767SBrooks Davis.Fa lowfd
46*8269e767SBrooks Davisfrom the per-process object reference table.
47*8269e767SBrooks DavisAny errors encountered while closing file descriptors are ignored.
48*8269e767SBrooks Davis.Pp
49*8269e767SBrooks DavisThe
50*8269e767SBrooks Davis.Fn close_range
51*8269e767SBrooks Davissystem call deletes all open file descriptors between
52*8269e767SBrooks Davis.Fa lowfd
53*8269e767SBrooks Davisand
54*8269e767SBrooks Davis.Fa highfd
55*8269e767SBrooks Davisinclusive, clamped to the range of open file descriptors.
56*8269e767SBrooks DavisAny errors encountered while closing file descriptors are ignored.
57*8269e767SBrooks DavisSupported
58*8269e767SBrooks Davis.Fa flags :
59*8269e767SBrooks Davis.Bl -tag -width ".Dv CLOSE_RANGE_CLOEXEC"
60*8269e767SBrooks Davis.It Dv CLOSE_RANGE_CLOEXEC
61*8269e767SBrooks DavisSet the close-on-exec flag on descriptors in the range instead of closing them.
62*8269e767SBrooks Davis.El
63*8269e767SBrooks Davis.Sh RETURN VALUES
64*8269e767SBrooks DavisUpon successful completion,
65*8269e767SBrooks Davis.Fn close_range
66*8269e767SBrooks Davisreturns a value
67*8269e767SBrooks Davisof 0.
68*8269e767SBrooks DavisOtherwise, a value of -1 is returned and the global variable
69*8269e767SBrooks Davis.Va errno
70*8269e767SBrooks Davisis set to indicate the error.
71*8269e767SBrooks Davis.Sh ERRORS
72*8269e767SBrooks DavisThe
73*8269e767SBrooks Davis.Fn close_range
74*8269e767SBrooks Davissystem call
75*8269e767SBrooks Daviswill fail if:
76*8269e767SBrooks Davis.Bl -tag -width Er
77*8269e767SBrooks Davis.It Bq Er EINVAL
78*8269e767SBrooks DavisThe
79*8269e767SBrooks Davis.Fa highfd
80*8269e767SBrooks Davisargument is lower than the
81*8269e767SBrooks Davis.Fa lowfd
82*8269e767SBrooks Davisargument.
83*8269e767SBrooks Davis.It Bq Er EINVAL
84*8269e767SBrooks DavisAn invalid flag was set.
85*8269e767SBrooks Davis.El
86*8269e767SBrooks Davis.Sh SEE ALSO
87*8269e767SBrooks Davis.Xr close 2
88*8269e767SBrooks Davis.Sh HISTORY
89*8269e767SBrooks DavisThe
90*8269e767SBrooks Davis.Fn closefrom
91*8269e767SBrooks Davisfunction first appeared in
92*8269e767SBrooks Davis.Fx 8.0 .
93