26 .\"
  27 .\" The contents of this file are subject to the terms of the
  28 .\" Common Development and Distribution License (the "License").
  29 .\" You may not use this file except in compliance with the License.
  30 .\"
  31 .\" You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
  32 .\" or http://www.opensolaris.org/os/licensing.
  33 .\" See the License for the specific language governing permissions
  34 .\" and limitations under the License.
  35 .\"
  36 .\" When distributing Covered Code, include this CDDL HEADER in each
  37 .\" file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  38 .\" If applicable, add the following below this CDDL HEADER, with the
  39 .\" fields enclosed by brackets "[]" replaced with your own identifying
  40 .\" information: Portions Copyright [yyyy] [name of copyright owner]
  41 .\"
  42 .\"
  43 .\" Copyright 1989 AT&T
  44 .\" Copyright (c) 1997, The Open Group. All Rights Reserved.
  45 .\" Portions Copyright (c) 2002, Sun Microsystems, Inc. All Rights Reserved.

  46 .\"
  47 .TH UNLOCKPT 3C "Aug 14, 2002"
  48 .SH NAME
  49 unlockpt \- unlock a pseudo-terminal master/slave pair
  50 .SH SYNOPSIS
  51 .LP
  52 .nf
  53 #include <stdlib.h>
  54 
  55 \fBint\fR \fBunlockpt\fR(\fBint\fR \fIfildes\fR);
  56 .fi
  57 
  58 .SH DESCRIPTION
  59 .sp
  60 .LP
  61 The \fBunlockpt()\fR function unlocks the slave pseudo-terminal device
  62 associated with the master to which \fIfildes\fR refers.
  63 .sp
  64 .LP
  65 Portable applications must call \fBunlockpt()\fR before opening the slave side
  66 of a pseudo-terminal device.
  67 .SH RETURN VALUES
  68 .sp
  69 .LP
  70 Upon successful completion, \fBunlockpt()\fR returns \fB0\fR. Otherwise, it
  71 returns \fB\(mi1\fR and sets \fBerrno\fR to indicate the error.
  72 .SH ERRORS
  73 .sp
  74 .LP
  75 The \fBunlockpt()\fR function may fail if:
  76 .sp
  77 .ne 2
  78 .na
  79 \fB\fBEBADF\fR\fR
  80 .ad
  81 .RS 10n
  82 The \fIfildes\fR argument is not a file descriptor open for writing.
  83 .RE
  84 
  85 .sp
  86 .ne 2
  87 .na
  88 \fB\fBEINVAL\fR\fR
  89 .ad
  90 .RS 10n
  91 The \fIfildes\fR argument is not associated with a master pseudo-terminal
  92 device.
  93 .RE
  94 
  95 .SH ATTRIBUTES
  96 .sp
  97 .LP
  98 See \fBattributes\fR(5) for descriptions of the following attributes:
  99 .sp
 100 
 101 .sp
 102 .TS
 103 box;
 104 c | c
 105 l | l .
 106 ATTRIBUTE TYPE  ATTRIBUTE VALUE
 107 _
 108 Interface Stability     Standard
 109 _
 110 MT-Level        Safe
 111 .TE
 112 
 113 .SH SEE ALSO
 114 .sp
 115 .LP
 116 \fBopen\fR(2), \fBgrantpt\fR(3C), \fBptsname\fR(3C), \fBattributes\fR(5),
 117 \fBstandards\fR(5)
 118 .sp
 119 .LP
 120 \fISTREAMS Programming Guide\fR

  26 .\"
  27 .\" The contents of this file are subject to the terms of the
  28 .\" Common Development and Distribution License (the "License").
  29 .\" You may not use this file except in compliance with the License.
  30 .\"
  31 .\" You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
  32 .\" or http://www.opensolaris.org/os/licensing.
  33 .\" See the License for the specific language governing permissions
  34 .\" and limitations under the License.
  35 .\"
  36 .\" When distributing Covered Code, include this CDDL HEADER in each
  37 .\" file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  38 .\" If applicable, add the following below this CDDL HEADER, with the
  39 .\" fields enclosed by brackets "[]" replaced with your own identifying
  40 .\" information: Portions Copyright [yyyy] [name of copyright owner]
  41 .\"
  42 .\"
  43 .\" Copyright 1989 AT&T
  44 .\" Copyright (c) 1997, The Open Group. All Rights Reserved.
  45 .\" Portions Copyright (c) 2002, Sun Microsystems, Inc. All Rights Reserved.
  46 .\" Copyright 2022 Oxide Computer Company
  47 .\"
  48 .Dd February 5, 2022
  49 .Dt UNLOCKPT 3C
  50 .Os
  51 .Sh NAME
  52 .Nm unlockpt
  53 .Nd unlock a pseudo-terminal device pair
  54 .Sh SYNOPSIS
  55 .In stdlib.h
  56 .Ft int
  57 .Fo unlockpt
  58 .Fa "int fildes"
  59 .Fc
  60 .Sh DESCRIPTION
  61 When a pseudo-terminal manager device is opened, whether through
  62 .Xr posix_openpt 3C
  63 or
  64 .Xr open 2
  65 on a
  66 .Xr ptm 7D
  67 device, the subsidiary device begins operation in a locked state.
  68 The
  69 .Fn unlockpt
  70 function unlocks the pseudo-terminal subsidiary device associated with the
  71 manager device to which
  72 .Fa fildes
  73 refers.
  74 .Pp
  75 Portable applications must call
  76 .Fn unlockpt
  77 before opening the pseudo-terminal subsidiary device.
  78 .Sh RETURN VALUES
  79 .Rv -std unlockpt
  80 .Sh EXAMPLES
  81 See
  82 .Xr posix_openpt 3C
  83 for an example that includes a call to
  84 .Fn unlockpt .
  85 .Sh ERRORS
  86 The
  87 .Fn unlockpt
  88 function may fail if:
  89 .Bl -tag -width Er
  90 .It Er EBADF
  91 The
  92 .Fa fildes
  93 argument is not a file descriptor open for writing.
  94 .It Er EINVAL
  95 EINVAL
  96 The
  97 .Fa fildes
  98 argument is not associated with a pseudo-terminal manager device.
  99 .El
 100 .Sh INTERFACE STABILITY
 101 .Sy Committed
 102 .Sh MT LEVEL
 103 .Sy Safe
 104 .Sh SEE ALSO
 105 .Xr open 2 ,
 106 .Xr grantpt 3C ,
 107 .Xr posix_openpt 3C ,
 108 .Xr ptsname 3C ,
 109 .Xr attributes 5 ,
 110 .Xr standards 5 ,
 111 .Xr ptm 7D