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Search function does not work in perl

I tried the below code snippet and the search function is not working.

funct("ls -ltr /scratch/dummy/dum*");

sub funct {

print "\nRecording\n";
open(SENSOR_LIST1, "$_[0] |") || die "Failed to read sensor list: $!\n";
for $sensor_line1 (<SENSOR_LIST1>) {
   print "$sensor_line1";
}
my $pos = tell SENSOR_LIST1;
print "\nposition is $pos"; #Here the position is 613

print "\nRecording again";
seek (SENSOR_LIST1, SEEK_SET, 0);
$pos = tell SENSOR_LIST1; # Here again the position is 613, even after a seek
print "\nposition now is $pos";

for $sensor_line1 (<SENSOR_LIST1>) {
        print "$sensor_line1";
    }
close SENSOR_LIST1;
}

Note. All search options don't work.

Output:

The position does not change even after searching. It remains in 613.

Can you guys check and let me know what the problem is?

Thank.

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2 answers


You cannot search for a pipe.

Use a temporary file or keep the data in memory.



Your choice of the best solution

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Try writing the output of your command ls

to a file and opening that file instead of reading the command output directly. You cannot seek

on a transient data stream (like the output of a command), only on data that still exists after reading (like a file).



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