Hi, Monks, I beg your wisdom. I have below leg of code. I execute in rc3 script. When it comes to line 12 it seems the script hangs there for more than 20 hours. See detailed log information below the code. Please be aware that I execute this script in various machines without any problems. Only in this IBM machine with InReach TTY console connected I get this issue. 

      1 sub ptrace {
      2   my ($msg, $level) = @_;
      3   $msg = pdate()." ".$msg;
      4   ptrace_wo_date($msg, $level);
      5 }
      6
      7 sub ptrace_wo_date {
      8   my ($msg, $level) = @_;
      9   $level = defined $level ? $level : $norm_trace;
     10   if ($traceLevel >= $level) {
     11     if ($ttymode) {
     12       print "$msg\n";
     13     }
     14     if ($log_opened) {
     15       print $logfh "$msg\n";
     16     }
     17   }
     18 }
     19
     20 sub plog {
     21   my $msg = shift;
     22   if ($ttymode) {
     23     $msg = pdate()." ".$msg;
     24   }
     25   if ($log_opened) {
     26     print $logfh "$msg\n";
     27   }
     28 }
     29
     30 # Main part
     31
     32 my $pit_trace = "/tmp/pit.trace";
     33 my $cmd = "/tmp/FMinstall.sh"
     34 ptrace("-I- executing: \n\t$cmd");
     35 system("$cmd > /tmp/instappcmd.out 2>&1");
     36 my $res = $? >> 8;
     37 my $pitres = readFile("/tmp/instappcmd.out");
     38 unlink "/tmp/instappcmd.out";
     39
     40 # log result and pit trace if any
     41 ptrace("  execution trace:\n$pitres");
     42
     43 if ( -f $pit_trace ) {
     44   $pitres = readFile($pit_trace);
     45   plog($pitres);
     46 }

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Below is the log from the above code. Lines 1 and 2 are print on 2/14, and it hangs there. After 20 hours when I login into the console of the machine lines 4 and later come out. From the time stamp on line 4 we can see the 3rd line of code should be executed on 2/14, then the code goes into the ptrace_wo_date() function, and comes to code on line 12, but it hangs there for 20 hours when I login on 2/15 it resumes. Then the code comes to line 45 and plog() prints the time stamp in below log line 21, which is 2/15.

My question is what is the possible reasons for the print() hangs. Why it resumes when I login on the console. I am on IBM machine with Console Access through terminal Server InReach MRV Port 3122. Appreciate your any comments on this in advance. 

      1 2013/02/14 16:25:20 -I- executing:
      2     /tmp/FMinstall.sh
      3
      4 2013/02/14 16:50:12   execution trace:
      5
      6 Execution of FMinstall.sh ...
      7
      8 2013-02-14 16:25:22     INFO  Stopping FM
      9 2013-02-14 16:25:22     INFO  FM instance name: player1
     10 Last login: Thu Feb 14 16:24:16 GMT 2013 on console
     11 Instance player1 is already in the STOPPED state.
     12 Last login: Thu Feb 14 16:24:16 GMT 2013 on console
     13 2013-02-14 16:25:23     INFO  FM Stopped
     14
     15 -I- Stopping FM player2 instance
     16
     17 2013-02-14 16:25:23     INFO  Stopping FM
     18 2013-02-14 16:25:23     INFO  FM instance name: player2
     19 ... ...
     20
     21 2013/02/15 12:33:27 2013/02/14 16:50:12:Audit:event(2)::SYSTEM
+():==================================================
     22 2013/02/14 16:50:12:Audit:event(2)::SYSTEM(): Starting the Aud
+it tool.
     23 2013/02/14 16:50:12:Audit:event(2)::SYSTEM():=================
+=================================
     24 2013/02/14 16:50:12:Audit:debug(4)::RepositoryXml.parseReposit
+oryFile():Reading file </usr/repository/products.xml>.
     25 2013/02/14 16:50:12:Audit:debug(4)::Repository.Repository():Co
+ntent of repository :

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In reply to print() function hang for long time by dengguochen2003

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