.TH ISUP 1 "April 20, 2002" CSLib "CSLib Utilities"
.nh
.SH NAME
isup \- Find out if a machine is up by trying a TCP/IP connection
.SH SYNOPSIS
.B isup
[ \fB\-p\fP ] \fBhost\fP [ \fBport\fP ]
.SH DESCRIPTION
.B isup
tries to create a TCP/IP connection to \fBhost\fP (optionally on port 
\fBport\fP, default is TCP 7, i.e. echo). If the machine is up (i.e.
the connection is accepted, or refused), then zero (success) is returned.
A non-zero error code is returned if the connection fails.
.TP
\fB\-p\fP
Also print out an explanatory line of whether the machine is available
or not, and if not, what the error was.
.SH AUTHOR
.B isup
was written by Alan Ford <ajf101@ecs.soton.ac.uk> <alan@whirlnet.co.uk>.
.SH SEE ALSO
.BR connect (3)