ssh-agent Command Line Options
The syntax for ssh-agent is:
ssh-agent [-c] [-d debug_level] [-h] [-k] [-s] [-t timeout] [-V] [command]
Options are available in both a single-character form (such as -o) and a descriptive equivalent (--option). Single characters are shown here. To view the descriptive equivalents, use the -h command line option.
-c
Forces the shell to be csh. By default ssh-agent uses the SHELL environment variable to determine which shell to invoke. This option overrides the default behavior.
-d debug_level
Sets the debug level. Increasing the value increases the amount of information displayed. Use 1, 2, 3, or 99. (Values 4-98 are accepted, but are equivalent to 3.)
-h
Displays a brief summary of command options.
-k
Kills the current agent (given by the SSH_AGENT_PID environment variable).
-s
Forces the shell to be sh. By default ssh-agent uses the SHELL environment variable to determine which shell to invoke. This option overrides the default behavior.
-t timeout
Sets a default timeout for any key added to the agent. Keys are deleted after the specified timeout. By default keys have no timeout limit, which is equivalent to setting a timeout value of zero(0). (You can also specify timeouts when you add keys by using the ssh-add -t option, which overrides this setting.)
By default, the timeout value is set in minutes. You can specify other units using this syntax:
n<unit>[n<unit>…]
Where unit can be: s (seconds), m (minutes), h (hours), d (days), or w (weeks). (Upper or lower case units are both accepted with the same meaning.) For example:
3600s= 3600 seconds (1 hour)2w= 2 weeks2d4h= 2 days and 4 hours
-V
Displays product name and version information and exits. If other options are specified on the command line, they are ignored.