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Dev

Device manager (QNX)

Syntax:

Dev [-n max_devices] [-N prefix] &

Options:

-n max_devices
The maximum number of terminal devices to support (default is 64).
-N prefix
The directory name to register in the pathname space. (default is /dev)

Description:

The Dev manager is responsible for managing all terminal devices in a QNX system.

Once Dev is started, the driver processes may be started. The drivers register themselves with Dev, making the hardware they control available to the system as additional devices. Some of the common drivers shipped with QNX are:

Driver Description
Dev.ansi console I/O (ANSI terminal emulation is default; also supports QNX terminal emulation)
Dev.con console I/O (QNX terminal emulation is default; also supports ANSI terminal emulation)
Dev.par parallel I/O
Dev.pty pseudo tty devices
Dev.ser serial I/O

Dev always supports the NULL device (called /dev/null); this device always takes up one of the device entries (-n option).


Note:

The Dev manager must be run as root.


Examples:

Start Dev; use defaults:

    Dev &

Allow 100 devices:

   Dev -n 100 &

Files:

Dev closes its standard input, standard output, and standard error immediately upon startup.

Dev adopts the directory /dev in the pathname prefix tree of the node it is run on. The special NULL device, /dev/null will also appear.

Exit status:

Dev does not normally terminate. Because of its importance in the system (especially a standalone one), Dev will choose to reduce its memory requirements by reducing the number of devices it will support instead of terminating with an error. However, there are still cases where Dev will exit, such as in the case of an invalid command-line parameter, failure to allocate internal structures sufficient for the support of at least a single device, and failure to attach the /dev prefix with Proc.

>0
An error occurred in startup.

See also:

Dev.*, modem, Mouse, stty, tinit

Installation & Configuration


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