I have tried something like this below but the problem is sometimes the subroutines executes incorrectly means i am writing an output to the file It could not able to do that successfully.

There are at least 3 problems with your post:

1. The code you have posted is incomplete.

   You have no use threads;

   You don't show where the variables $outputfile1 & $outfutfile2 are set.

   There are also a bunch of other variables that aren't declared:

   Global symbol "$outputfile1" requires explicit package name at junk.pl
   + line 28.
   Global symbol "$app_num_common" requires explicit package name at junk
   +.pl line 46.
   Global symbol "$app_string_common" requires explicit package name at j
   +unk.pl line 54.
   Global symbol "$app_num_iis" requires explicit package name at junk.pl
   + line 64.
   Global symbol "$app_string_iis" requires explicit package name at junk
   +.pl line 71.
   Global symbol "$app_num_powerpath" requires explicit package name at j
   +unk.pl line 79.
   Global symbol "$app_string_powerpath" requires explicit package name a
   +t junk.pl line 86.
   Global symbol "$outputfile2" requires explicit package name at junk.pl
   + line 115.
   [download]

2. You do not explain what you mean by "sometimes the subroutines executes incorrectly".
3. And you need to get some help with phrasing your post in English, because it is very difficult to understand what you mean by:

   "means i am writing an output to the file It could not able to do that successfully."

Unless the code is complete; we cannot work out what might be wrong from that.

Unless you explain what you mean by "executes incorrectly", we can only guess what might be going wrong.

We realise that English is not your native tongue, but if we are to understand you, we'll need you to get some help with it.