Yes, you are right. The error is this: 
pp2@europa:~/LGRID-Machine/examples/matrixproduct/open2$ ./matrix_grid
+.pl
Can't open perl script "/tmp/gridmachine_driver_matrixZNJuj": No such 
+file or directory
Use of uninitialized value in eval "string" at ./matrix_grid.pl line 1
+88, <GEN16> chunk 171.
Use of uninitialized value in eval "string" at ./matrix_grid.pl line 1
+88, <GEN16> chunk 171.
Use of uninitialized value in eval "string" at ./matrix_grid.pl line 1
+88, <GEN16> chunk 171.
Wrong result from process 0 in machine bw
pp2@europa:~/LGRID-Machine/examples/matrixproduct/open2$ Can't open pe
+rl script "/tmp/gridmachine_driver_matrixj64e3": No existe el fichero
+ o el directorio

pp2@europa:~/LGRID-Machine/examples/matrixproduct/open2$

[download]
If I uncomment the sleep in 
pp2@europa:~/LGRID-Machine/examples/matrixproduct/open2$ sed -ne '153,
+168p' matrix_grid.pl
foreach (@str_handles) {
  my $pid = $pm->start and next;

  $b = syswrite $_->{handle},
           join(" ",
                  $_->{chunksize},
                  $_->{A_cols},
                  @A_lines[$_->{start}.. $_->{end}],
                  @B_lines,
                  "\cN"
               );
  # Wait until the writing has finished
  # sleep(1);
  $pm->finish;
}

[download]
It goes OK: 

pp2@europa:~/LGRID-Machine/examples/matrixproduct/open2$ ./matrix_grid
+.pl
Process 0: machine = bw received result
Process 1: machine = beowulf received result
Process 2: machine = europa received result
Process 3: machine = orion received result
Elapsed Time: 1.148361 seconds

[download]
I know is still very cryptic. Apologies.

Casiano

In reply to Re^4: How I'm sure syswrite has finished? by casiano
in thread How I'm sure syswrite has finished? by casiano

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.