The PostgreSQL 8.1.5 sources can be obtained by anonymous FTP from ftp://ftp.postgresql.org/pub/source/v8.1.5/postgresql-8.1.5.tar.gz. Other download options can be found on our website: https://www.postgresql.org/download/. After you have obtained the file, unpack it:
gunzip postgresql-8.1.5.tar.gz tar xf postgresql-8.1.5.tar
This will create a directory postgresql-8.1.5 under the current directory with the PostgreSQL sources. Change into that directory for the rest of the installation procedure.
