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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 79740 by ErNci on Sunday 31st of July 2005 06:25:47 AM
Old 07-31-2005
Yes, as tjlist said, the percecitonal way really should be

if ( ( system("/bin/chio -f $changerDevice move slot ".($tape-1)." drive 0
") ) / 256 ) {
print "$progname: cannot '/bin/chio -f $changerDevice move' tape
$tape into drive 0\n";
exit(2);
}
print LOG &do_time(), ": leave: Load\n";

And in the first example, the 2nd example would be

sub getDate {
print "start date\n";
my $buff = '';
if ( ($buff = `/bin/date`) eq ''){
print "can't get date\n";
exit(2);
}
print "finish date\n";
}
 

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LEARN ABOUT SUNOS

tcopy

tcopy(1)							   User Commands							  tcopy(1)

NAME

       tcopy - copy a magnetic tape

SYNOPSIS

       tcopy source [destination]

DESCRIPTION

       The  tcopy  utility copies the magnetic tape mounted on the tape drive specified by the source argument. The only assumption made about the
       contents of a tape is that there are two tape marks at the end.

       When only a source drive is specified, tcopy scans the tape, and displays information about the sizes of records and tape files.  If a des-
       tination  is  specified,  tcopy makes a copies the source tape onto the destination tape, with blocking preserved. As it copies, tcopy pro-
       duces the same output as it does when only scanning a tape.

       The tcopy utility requires the use of Berkeley-compatible device names. For example,

       example% tcopy /dev/rmt/1b /dev/rmt/2b

ATTRIBUTES

       See attributes(5) for descriptions of the following attributes:

       +-----------------------------+-----------------------------+
       |      ATTRIBUTE TYPE	     |	    ATTRIBUTE VALUE	   |
       +-----------------------------+-----------------------------+
       |Availability		     |SUNWesu			   |
       +-----------------------------+-----------------------------+

SEE ALSO

       mt(1), ioctl(2), attributes(5)

NOTES

       tcopy will only run on systems supporting an associated set of  ioctl(2) requests.

SunOS 5.10							    10 Mar 2000 							  tcopy(1)
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