The
watch
utility allows the user to examine all data coming through a specified tty
using the
snp(4)
device.
If the
snp(4)
device is not available,
watch
will attempt to load the module
(
snp).
The
watch
utility writes to standard output.
The options are as follows:
-c
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|
Reconnect on close.
If the tty observed by
watch
is closed, automatically reattach to the same tty.
If this option is not specified,
watch
will request a new tty if running in interactive mode or exit if running
without a controlling tty.
|
-f snpdev
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If this option is specified,
watch
will use
snpdev
as the
snp(4)
device.
Without this option,
watch
will attempt to find the next available
snp(4)
device.
|
-i
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Force interactive mode.
Interactive mode is a default if
watch
is started from a tty.
If output is redirected to a file, interactive mode can still be requested
by specifying this option.
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-n
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Disable the ability to switch the watched tty interactively.
This disables
both change requests made with <control-X> as well as automatic prompting
when the current tty is closed or overflows.
In all cases where a prompt
would be displayed,
watch
will exit.
The reconnect flags are unaffected by
this option.
When this flag is used, <control-X> is passed through to the terminal.
|
-o
|
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Reconnect on overflow.
The behavior of
watch
if the observed tty overflows is similar to the behavior if the observed tty
is closed.
For more info see
snp(4).
|
-t
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Print the date and time when observation of a given tty is started.
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-W
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Allow write access to observed tty.
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tty
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Tty may be specified as a tty-style device, such as a pseudo tty device,
a virtual console, or a serial line, etc.
Names may be preceded by
/dev/.
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