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Full Discussion: Perl - backticks v system in if statements
Top Forums Shell Programming and Scripting Perl - backticks v system in if statements Post 79600 by gjkeenan on Thursday 28th of July 2005 09:03:45 PM
Old 07-28-2005
Thanks for explaining that. Makes sense now.

The date thing was just an example. The actual code is from this tape changer script and I couldn't understand the logic if the chio command ran OK why the print and exit didn't run after it.

Code:
if ( system("/bin/chio -f $changerDevice move slot ".($tape-1)." drive 0
") ) {
    print "$progname: cannot '/bin/chio -f $changerDevice move' tape
 $tape into drive 0\n";
    exit(2);
}
print LOG &do_time(), ": leave: Load\n";

gjkeenan
 

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LEARN ABOUT SUSE

sensors

sensors(1)							Linux User's Manual							sensors(1)

NAME

       sensors - print sensors information

SYNOPSIS

       sensors [ options ] [ chips ]
       sensors -s [ chips ]
       sensors --bus-list

DESCRIPTION

       sensors is used to show the current readings of all sensor chips.
       sensors -s is used to set all limits as specified in the configuration file.
       sensors --bus-list is used to generate bus statements suitable for the configuration file.

OPTIONS

       -c config-file
	      Specify a configuration file. If no file is specified, the libsensors default configuration file is used. Use `-c /dev/null' to tem-
	      porarily disable this default configuration file.

       -h     Print a help text and exit.

       -s     Evaluate all `set' statements in the configuration file and exit. You must be `root' to do this. If this parameter is not specified,
	      no `set' statement is evaluated.

       -A     Do not show the adapter for each chip.

       -u     Raw output. This mode is only meant for debugging.

       -v     Print the program version and exit.

       -f     Print the temperatures in degrees Fahrenheit instead of Celsius.

       --bus-list
	      Generate	bus  statements  suitable for using in sensors.conf. Such bus statements are only needed if you have several chips sharing
	      the same address on different buses of the same type. As bus numbers are usually not guaranteed to be  stable  over  reboots,  these
	      statements let you refer to each bus by its name rather than numbers.

FILES

       /etc/sensors3.conf
       /etc/sensors.conf
	      The system wide configuration file. See sensors.conf(5) for further details.

SEE ALSO

       sensors.conf(5)

AUTHOR

       Frodo Looijaard and the lm_sensors group http://www.lm-sensors.org/

lm-sensors 3							   October 2007 							sensors(1)
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