Re: Threads and print

my @threads = map {
    ## create the workers passing the log file handle and semaphore
    threads->create( \&worker, $log, \$logSem,$_*$N, $_*$N + $N -1);
} 0 .. 5; ## 5 threads each processing 100 "files"
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...<hem>that's 6 threads, shirly ?

To process $from..$to in $t threads, how about:

my @threads = map{
  threads->create( \&worker, $log, \$logSem, $from + ($_ - 1), $t, $to
+) ;
} 1 .. $t ;
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and in the thread:

  my( $log, $semRef, $from, $step, $to ) = @_;
  for (my $file = $from ; $file <= $to ; $file += $step) {
  ......
  } ;
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which deals with the number of files not being an exact multiple of the number of threads, and copes with $from..$to range where $from is not zero and $to is included in the range...

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Re^2: Threads and print by sandy1028 (Sexton) on Apr 16, 2009 at 09:52 UTC
Can you please tell me how to create single log file per thread and the values are in sequence order.	[reply]
Re^3: Threads and print by cdarke (Prior) on Apr 16, 2009 at 11:40 UTC
'ang about gov'ner, I thought you wanted to have all the threads writing to the same log file? No? OK, then open a new log file in the worker function. Use some unique value passed as a parameter as part of the file name.	[reply]
Re^4: Threads and print by sandy1028 (Sexton) on Apr 17, 2009 at 04:57 UTC
Hi, Here I used the code for writing into single log file. But the threads are not printing the "Processesing file" in sequence order and the lines overlap even if I use lock. How can i avoid this? #! perl -slw use strict; use threads; use threads::shared; our $from=1; our $to=400020; our $t=5; sub worker { my $tid = threads->tid; # my( $log, $semRef, $from, $to ) = @_; my( $log, $semRef, $from, $step, $to ) = @_; for (my $file = $from ; $file <= $to ; $file += $step) { lock $$semRef; printf $log "The threads is [%2d] Processesing file%3d\n",$tid, $file +; } } ## A shared variable used as a semaphore for the log file resource my $logSem :shared; ## Open the log file in the main thread open my $log, '>', 'myLog' or die $!; my @threads = map{ threads->create( \&worker, $log, \$logSem, $from + ($_ - 1), $t, $to +) ; } 1 .. $t ; ## Wait till they are done $_->join for @threads; ## close the log close $log; [download] `The threads is [ 1] Processesing file16436 The threads is [ 1] Processesing file16441 The threads is [ 1] Processesing file 2] Processesing file2462 The threads is [ 2] Processesing file2467 The threads is [ 2] Processesing file2472` [download]	[reply] [d/l] [select]
Re^4: Threads and print by sandy1028 (Sexton) on Apr 20, 2009 at 06:06 UTC
In place of print $log ("The threads is $tid Processing file, $file"); How to print the file names of the directory. #! perl -slw use strict; use threads; use threads::shared; our $N \|\|= 100; our $t=5; our $from=1; our $filenames; sub worker { my $tid = threads->tid; # my( $log, $semRef, $from, $to ) = @_; my( $log, $semRef, $from, $step, $to ) = @_; for (my $file = $from ; $file <= $to ; $file += $step) { lock $$semRef; print $log ("The threads is $tid Processing file, $file"); } } ## A shared variable used as a semaphore for the log file resource my $logSem :shared; ## Open the log file in the main thread open my $log, ">myLog" or die $!; my @threads = map{ threads->create( \&worker, $log, \$logSem, $from + ($_ - 1), $t, $to +) ; } 1 .. $t ; ## Wait till they are done $_->join for @threads; ## close the log close $log; [download]	[reply] [d/l]