'\" te
.\"  Copyright 1989 AT&T  Copyright (c) 2002, Sun Microsystems, Inc.  All Rights Reserved
.TH isastream 3C "24 Jul 2002" "SunOS 5.11" "Standard C Library Functions"
.SH NAME
isastream \- test a file descriptor
.SH SYNOPSIS
.LP
.nf
#include <stropts.h>

\fBint\fR \fBisastream\fR(\fBint\fR \fIfildes\fR);
.fi

.SH DESCRIPTION
.sp
.LP
The  \fBisastream()\fR function determines if a file descriptor represents a STREAMS file. The \fIfildes\fR argument refers to an open file descriptor.
.SH RETURN VALUES
.sp
.LP
Upon successful completion, \fBisastream()\fR returns \fB1\fR if \fIfildes\fR represents a STREAMS file, and \fB0\fR if it does not.  Otherwise, \fB\(mi1\fR is return and \fBerrno\fR is set to indicate the error.
.SH ERRORS
.sp
.LP
The \fBisastream()\fR function will fail if:
.sp
.ne 2
.mk
.na
\fB\fBEBADF\fR\fR
.ad
.RS 9n
.rt  
The \fIfildes\fR argument is not a valid file descriptor.
.RE

.SH ATTRIBUTES
.sp
.LP
See \fBattributes\fR(5) for descriptions of the following attributes:
.sp

.sp
.TS
tab() box;
cw(2.75i) |cw(2.75i) 
lw(2.75i) |lw(2.75i) 
.
ATTRIBUTE TYPEATTRIBUTE VALUE
_
Interface StabilityCommitted
_
MT-LevelMT-Safe
_
StandardSee \fBstandards\fR(5).
.TE

.SH SEE ALSO
.sp
.LP
\fBattributes\fR(5), , \fBstandards\fR(5), \fBstreamio\fR(7I)
.sp
.LP
\fISTREAMS Programming Guide\fR