tcpclient

Section: User Commands (1)
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NAME

tcpclient - create an outgoing TCP connection

 

SYNOPSIS

tcpclient [ -46hHrRdDqQv ] [ -ilocalip ] [ -plocalport ] [ -Ttimeoutconn ] [ -llocalname ] [ -ttimeoutinfo ] [ -Iifname ] host port program [ arg ... ]

 

DESCRIPTION

tcpclient attempts to connect to a TCP server. If it is successful, it runs program with the given arguments, with descriptor 6 reading from the network and descriptor 7 writing to the network.

The server's address is given by host and port. host may be 0, which is identical to 127.0.0.1, or ::1 referring to the IPv6 loopback address, a compactified IPv6 address, a dotted-decimal IPv4 address, or a host name. If a host name is given, tcpclient facilitates a DNS lookup and tries each address in turn. port may be a numeric port number or a port name.

tcpclient sets up several environment variables, as described in tcp-environ(5).

 

OPTIONS

-4
Use IPv4 connections only.
-6
Force IPv6 mode for connections. This will set PROTO to TCP6 and put IPv4-mapped IPv6 addresses in TCPLOCALIP and TCPREMOTEIP.
-ilocalip
Use localip as the IP address for the local side of the connection; quit if localip is not available.
-plocalport
Use localport as the port number for the local side of the connection; quit if localport is not available.
-Iifname
Use ifname as the local network interface. This is only defined for IPv6 sockets and needed if you use link-local IPv6 addresses.
-Ttimeoutconn
Give up on the connection attempt after timeoutconn seconds. Default: 60. This timeout applies to each IP address tried.
-d
(Default.) Delay sending data for a fraction of a second whenever the remote host is responding slowly, to make better use of the network.
-D
Never delay sending data; enable TCP_NODELAY. This is appropriate for interactive connections.
-q
Quiet. Do not print any messages.
-Q
(Default.) Print error messages.
-v
Verbose. Print all available messages.
 

DATA-GATHERING OPTIONS

-h
(Default.) Look up the remote host name for TCPREMOTEHOST.
-H
Do not look up the remote host name; unset TCPREMOTEHOST.
-llocalname
Do not look up the local host name; use localname for TCPLOCALHOST.
-r
(Default.) Attempt to obtain TCPREMOTEINFO from the remote host.
-R
Do not attempt to obtain TCPREMOTEINFO from the remote host.
-ttimeoutinfo
Give up on the TCPREMOTEINFO connection attempt after timeoutinfo seconds. Default: 26.
 

ENVIRONMENT VARIABLES READ

tcpclient reads the environment variable DNSCACHEIP which can be used to specify the recursive DNS Resolver dynamically.  

ENVIRONMENT VARIABLE SET

tcplient will set:

PROTO to TCP or TCP6.

TCPLOCALIP and TCP6LOCALIP together with

TCPLOCALPORT and TCP6LOCALPORT. Also

TCPREMOTEIP and TCP6REMOTEIP is together provided with

TCPREMOTEPORT and TCP6REMOTEPORT. Finally,

TCPREMOTEHOST and

TCPREMOTEINFO is given.

 

SEE ALSO

date@(1), finger@(1), http@(1), mconnect(1), tcpcat(1), tcpserver(1), who@(1), tcp-environ(5)


 

Index

NAME
SYNOPSIS
DESCRIPTION
OPTIONS
DATA-GATHERING OPTIONS
ENVIRONMENT VARIABLES READ
ENVIRONMENT VARIABLE SET
SEE ALSO

This document was created by man2html, using the manual pages.
Time: 09:27:29 GMT, September 23, 2024