telnet [ ホスト名 [ポート番号]]
21:FTP 23:TELNET 25:SMTP 80:HTTPまた telnet は起動後、 telnet のプロンプトに対して、サブコマンドを入力する事が できます。以下におもなサブコマンドをまとめます。
# 他のOSが稼働するサーバへ接続した例 $ telnet vms002 Trying... Connected to vms002 Escape character is '^]'. V M S 0 0 2-- UNAUTHORIZED ACCESS IS PROHIBITED Username: YAKOSHI Password: +---+---+---+---+---+---+---+ | d | i | g | i | t | a | l | +---+---+---+---+---+---+---+ Last interactive login on Thursday, 11-APR-1991 14:18 Last non-interactive login on Thursday, 4-APR-1991 11:38 $ LOGOUT # SMTPサーバへ接続した例 $ telnet osaka 25 xx.xx.xx.xx に接続中... osaka に接続しました。 エスケープ文字: ^] 220 osaka Sendmail 5.65 (1.1.3.6) Mon, 5 Dec 1994 13:31:52 +0900 help 214-Commands: 214- HELO MAIL RCPT DATA RSET 214- NOOP QUIT HELP VRFY EXPN 214-For more info use "HELP". 214-To report bugs in the implementation contact eric@Berkeley.ARPA 214-or eric@UCB-ARPA.ARPA. 214-For local information contact postmaster at this site. 214 End of HELP info quit 221 osaka closing connection Connection closed by foreign host. # Webサーバへ接続した例 $ telnet www.google.com 80 Trying 66.249.89.104... Connected to www.google.com (66.249.89.104). Escape character is '^]'. GET / HTTP/1.0 (Enterは2回入力) HTTP/1.0 302 Found Location: http://www.google.co.jp/ Cache-Control: private Set-Cookie: PREF=ID=13117ea904c7a9f8:TM=1191135606:LM=1191135606:S=UARZViyaroZ6jKah; expires=Tue, 29-Sep-2009 07:00:06 GMT; path=/; domain=.google.com Content-Type: text/html Server: gws Content-Length: 221 Date: Sun, 30 Sep 2007 07:00:06 GMT Connection: Keep-Alive <HTML><HEAD><meta http-equiv="content-type" content="text/html;charset=utf-8"> <TITLE>302 Moved</TITLE></HEAD><BODY> <H1>302 Moved</H1> The document has moved <A HREF="http://www.google.co.jp/">here</A>. </BODY></HTML> Connection closed by foreign host.