Hi arun1581,
First of all: using PL/SQL for manipulating texts in an plain text-file is not the tool I would use. Much better (and easier to handle) form my expierinece is unsing Perl.
But if you prefere to use PL/SQL you must first make sure sure, that your have set the init.ora-parameter 'utl_file_dir' to a directory, which you can use. This is not dynamic, so you have to reboot the Instance after changing it.
furthermore read the documtenation of how to use the built-in package utl_file:
http://tahiti.oracle.com/pls/db901/d...?section=33316
basically you need to take care for:
1. havind a utl_file_dir defined and acces-rights to it
2. a file-handle
3. the open/close functions of utl_file package
4. the read/write operations from that package
hope it helps LaoDe