Hello Everyone! Can someone, Please, explain to me kind of weird phenomena. I have perl script below which I’m running on Sun/Solaris

Machine hardware:   sun4u
OS version:         5.8
Processor type:     sparc
Hardware:           SUNW,Sun-Fire-880
Perl version : This is perl, version 5.005_03 built for sun4-solaris
#!/bin/perl
#hostname.pl
use subs qw(getHostname LoginName HostEntry GetNetByName);
my $hostname="not defined";
print "hostname: $hostname\n";
print "*****\n";
getHostname;
print "****\n";

sub getHostname {
  #print "Hostname: ";
  system "/bin/hostname";
  #print "\n";
  #$hostname = system "/bin/hostname";
  #$hostname = exec "/bin/hostname";
  #$hostname = syscall "/bin/hostname";
  #print "Hostname: $hostname\n";
  return 0;
}
[download]

here is the output:

perl hostname.pl
hostname: not defined
*****
correct_UNIX_box_name
****
[download]

However, should I change subroutine to:

sub getHostname {
  $hostname = system "/bin/hostname";
  print "Hostname: ", $hostname, "\n";
  return 0;
}
[download]

the output will be:

perl hostname.pl
hostname: not defined
*****
correct_UNIX_box_name
Hostname: 0
****
[download]

Then in attempt to print output nicely, I made the following changes:

print "Hostname: ";
getHostname;

sub getHostname {
  system "/bin/hostname";
  return 0;
}
[download]

the output surprised me. I was under impression that Perl is a script language, which means it is being executed line by line… , so it should print out first:

Hostname:
[download]

and then on the same line:

correct_UNIX_box_name
[download]

but instead it reveres it and execute subroutine first and then print out line above. here is the output:

perl hostname.pl
hostname: not defined
*****
correct_UNIX_box_name
Hostname: ****
[download]

I don’t get it… can someone, please explain it? I’m trying to accomplish easy task: print out unix box name I’m currently in. May be someone can suggest another way to get it? The reason I inserted information about OS and UNIX machine is because I suspect it is platform dependant issue. I do not have such problem when I run the same script on Windows XP on PC - everything appears is expected.

Many Thanks in advance.

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