.\" -*-nroff-*-
.\"
.\" Manual for file descriptor flags
.\"
.\" (c) 1999, 2001, 2005, 2009, 2023, 2024 Straylight/Edgeware
.\"
.
.\"----- Licensing notice ---------------------------------------------------
.\"
.\" This file is part of the mLib utilities library.
.\"
.\" mLib is free software: you can redistribute it and/or modify it under
.\" the terms of the GNU Library General Public License as published by
.\" the Free Software Foundation; either version 2 of the License, or (at
.\" your option) any later version.
.\"
.\" mLib is distributed in the hope that it will be useful, but WITHOUT
.\" ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
.\" FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Library General Public
.\" License for more details.
.\"
.\" You should have received a copy of the GNU Library General Public
.\" License along with mLib.  If not, write to the Free Software
.\" Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307,
.\" USA.
.
.\"--------------------------------------------------------------------------
.so ../defs.man \" @@@PRE@@@
.
.\"--------------------------------------------------------------------------
.TH fdflags 3mLib "23 July 1999" "Straylight/Edgeware" "mLib utilities library"
.\" @fdflags
.
.\"--------------------------------------------------------------------------
.SH "NAME"
fdflags \- set file and file descriptor flags
.
.\"--------------------------------------------------------------------------
.SH "SYNOPSIS"
.
.nf
.B "#include <mLib/fdflags.h>"
.PP
.ta \w'\fBint fdflags('u
.BI "int fdflags(int " fd ,
.BI "	unsigned " fbic ", unsigned " fxor ,
.BI "	unsigned " fdbic ", unsigned " fdxor );
.fi
.
.\"--------------------------------------------------------------------------
.SH "DESCRIPTION"
.
.B fdflags
is a convenience function for setting file and file descriptor flags
using
.BR fcntl (2).
.PP
The file flags are read using
.BR F_GETFL ,
the new flags are calculated as
.sp 1
.RS
.I new-flags
=
.BI ( old-flags
.B &
.BI ~ fbic )
.B ^
.I fxor
.RE
.sp 1
and the result written back using
.BR F_SETFL .
.PP
Similarly the file descriptor flags are read using
.BR F_GETFD ,
the new flags calculated as
.sp 1
.RS
.I new-flags
=
.BI ( old-flags
.B &
.BI ~ fdbic )
.B ^
.I fdxor
.RE
.sp 1
and the result written back using
.BR F_SETFD .
.PP
If all went well,
.B fdflags
returns zero; if there was an error, \-1 is returned.
.
.\"--------------------------------------------------------------------------
.SH "EXAMPLES"
.
To set the non-blocking and close-on-exec flags:
.VS
fdflags(fd, O_NONBLOCK, O_NONBLOCK, FD_CLOEXEC, FD_CLOEXEC);
.VE
To clear the non-blocking and close-on-exec flags:
.VS
fdflags(fd, O_NONBLOCK, 0, FD_CLOEXEC, 0);
.VE
.sp -1
.
.\"--------------------------------------------------------------------------
.SH "SEE ALSO"
.
.BR mLib (3).
.
.\"--------------------------------------------------------------------------
.SH "AUTHOR"
.
Mark Wooding, <mdw@distorted.org.uk>
.
.\"----- That's all, folks --------------------------------------------------