tcpclient(1)tcpclient(1)NAMEtcpclient - creates an outgoing TCP connection.
SYNOPSIStcpclient [ opts ] host port prog
DESCRIPTION
opts is a series of getopt-style options. host is one argument. port
is one argument. prog consists of one or more arguments.
tcpclient attempts to connect to a TCP server. If it is successful, it
runs prog, with descriptor 6 reading from the network and descriptor 7
writing to the network. It also sets up several environment variables
(see tcp-environ(5) ).
The server's address is given by host and port. port may be a name
from /etc/services or a number. host may be 0, referring to the local
machine, or a dotted-decimal IP address, or a host name; it is fed
through qualification using dns_ip4_qualify.
If the server has several IP addresses, tcpclient tries each address in
turn.
OPTIONS
General options:
-q Quiet. Do not print error messages.
-Q (Default.) Print error messages.
-v Verbose. Print error messages and status messages.
Connection options:
-T x+y Give up on the connection attempt after x+y seconds. Default:
2+58. When a host has several IP addresses, tcpclient tries to
connect to the first IP address, waits x seconds, tries to con‐
nect to the second IP address, waits x seconds, etc.; then it
retries each address that timed out, waiting y seconds per
address. You may omit +y to skip the second try. Before version
0.88, tcpclient(1) will use only x (default: 60).
-i localip
Use localip as the IP address for the local side of the connec‐
tion; quit if localip is not available. Normally tcpclient lets
the operating system choose an address.
-p localport
Use localport as the TCP port for the local side of the connec‐
tion; quit if localport is not available. Normally tcpclient
lets the operating system choose a port.
-d Delay sending data for a fraction of a second whenever the
remote host is responding slowly. This is currently the default,
but it may not be in the future; if you want it, set it explic‐
itly.
-D Never delay sending data; enable TCP_NODELAY.
Data-gathering options:
-h (Default.) Look up the remote host name in DNS to set the envi‐
ronment variable $TCPREMOTEHOST.
-H Do not look up the remote host name in DNS; remove the environ‐
ment variable $TCPREMOTEHOST.
-l localname
Do not look up the local host name in DNS; use localname for the
environment variable $TCPLOCALHOST. A common choice for local‐
name is 0.
-r (Default.) Attempt to obtain $TCPREMOTEINFO from the remote
host.
-R Do not attempt to obtain $TCPREMOTEINFO from the remote host.
-t n Give up on the $TCPREMOTEINFO connection attempt after n sec‐
onds. Default: 26.
SEE ALSOtcpserver(1), tcprules(1), tcprulescheck(1), argv0(1), fixcrio(1),
recordio(1), rblsmtpd(1), who@(1), date@(1), finger@(1), http@(1), tcp‐
cat(1), mconnect(1), tcp-environ(5)
http://cr.yp.to/ucspi-tcp.html
tcpclient(1)
