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Top Forums Shell Programming and Scripting Meaning of "> /dev/null 2>&1" Post 302100930 by salanalani on Tuesday 26th of December 2006 01:09:50 AM
Old 12-26-2006
Question Meaning of "> /dev/null 2>&1"

Hi,

I am new into UNIX shell scripting and I am wondering what is the meaning of the below text which appears at the end of each line in the ".sh" file:

> /dev/null 2>&1

For example, the line below:

sh $HOME/stats/Rep777/Act_777.sh omc omc > /dev/null 2>&1

I know for sure what "sh $HOME/stats/Rep777/Act_777.sh omc omc" does mean but I don't have any idea about the rest which is " > /dev/null 2>&1".

Thanks in advance.
 

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device_maps(4)                                                     File Formats                                                     device_maps(4)

NAME
device_maps - device_maps file SYNOPSIS
/etc/security/device_maps DESCRIPTION
The device_maps file contains access control information about each physical device. Each device is represented by a one line entry of the form: device-name : device-type : device-list : where device-name This is an arbitrary ASCII string naming the physical device. This field contains no embedded white space or non- printable characters. device-type This is an arbitrary ASCII string naming the generic device type. This field identifies and groups together devices of like type. This field contains no embedded white space or non-printable characters. device-list This is a list of the device special files associated with the physical device. This field contains valid device special file path names separated by white space. The device_maps file is an ASCII file that resides in the /etc/security directory. Lines in device_maps can end with a `' to continue an entry on the next line. Comments may also be included. A `#' makes a comment of all further text until the next NEWLINE not immediately preceded by a `'. Leading and trailing blanks are allowed in any of the fields. The device_maps file must be created by the system administrator before device allocation is enabled. This file is owned by root, with a group of sys, and a mode of 0644. EXAMPLES
Example 1: A sample device_maps file # scsi tape st1: rmt: /dev/rst21 /dev/nrst21 /dev/rst5 /dev/nrst5 /dev/rst13 /dev/nrst13 /dev/rst29 /dev/nrst29 /dev/rmt/1l /dev/rmt/1m /dev/rmt/1 /dev/rmt/1h /dev/rmt/1u /dev/rmt/1ln /dev/rmt/1mn /dev/rmt/1n /dev/rmt/1hn /dev/rmt/1un /dev/rmt/1b /dev/rmt/1bn: FILES
/etc/security/device_maps SEE ALSO
allocate(1), bsmconv(1M), deallocate(1), dminfo(1M), list_devices(1) NOTES
The functionality described in this man page is available only if the Basic Security Module (BSM) has been enabled. See bsmconv(1M) for more information. SunOS 5.10 16 Jan 2001 device_maps(4)
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