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18 Chapter 1 Typing Commands
Using Telnet
Because it isn’t as secure as SSH, Telnet access isn’t enabled by default.
To enable Telnet access:
$ service telnet start
To disable Telnet access:
$ service telnet stop
Getting Online Help for Commands
Onscreen help is available for most commands and utilities.
Note: Not all techniques work for all commands, and some commands have no
onscreen help.
To view onscreen information about a command, try the following:
• Type the command without any parameters or options. This will often list a summary
of options and parameters you can use with the command.
Example:
$ sudo serveradmin
• Type man command, where command is the command you’re curious about. This
usually displays detailed information about the command, its options, parameters,
and proper use.
Example:
$ man serveradmin
For help using the man command, type:
$ man man
• Type the command followed by a -help, -h, --help, or help parameter.
Examples:
$ hdiutil help
$ dig -h
$ diff --help
LL2354.book Page 18 Monday, October 20, 2003 9:47 AM