Hi Van,
Following the usual untar of the aolserver3.3ad13 sources you should cd to the root/aolserver directory. What's puzzling of course is that the excerpt you've included apparently shows that you are in that directory.
Here's what I just tried, and it seems to work for me. I don't really know what to suggest, except to ensure that you're in the right directory, and have the right patch file (mine shows a length of 240840 bytes.) (and perhaps to play with that "5" (in the p5)). Perhaps someone else can explain differences or problems with patch....?
[nsadmin@web p0rn]# cd /tmp
[nsadmin@web aolserver]# ls -l /web/tag/download/AOLserverVirtualHostingPatches/13.file
-rw-r--r-- 1 theasher web 240840 Sep 19 04:28 /web/tag/download/AOLserverVirtualHostingPatches/13.file
[nsadmin@web aolserver]#
[nsadmin@web /tmp]# tar zxvf aol/aolserver33.ad13.src.tar.gz
root/
root/aolserver/
root/aolserver/doc/
. . .
root/arsdigita-aol3/make-dist.sh
root/arsdigita-aol3/make-src-dist.sh
[nsadmin@web /tmp]# cd root/aolserver/
[nsadmin@web aolserver]# ls -F
ChangeLog DISTRIBUTION.txt Makefile doc/ include/ nscgi/ nsd/ nslog/ nspd/ nssock/ nsvhr/ tcl/ tcl8.3.2/ thread/ windows-nsd.tcl
DISTRIBUTION.patch LICENSE.txt README encoding-doc.html index.html nscp/ nsext/ nsodbc/ nsperm/ nsunix/ scripts/ tcl7.6/ tests/ win32/
[nsadmin@web aolserver]# patch -p5 </web/tag/download/AOLserverVirtualHostingPatches/13.file
patching file `ChangeLog'
patching file `Makefile'
patching file `include/ns.h'
patching file `nsd/config.c'
patching file `nsd/conn.c'
patching file `nsd/dbinit.c'
patching file `nsd/dbtcl.c'
patching file `nsd/drv.c'
patching file `nsd/log.c'
patching file `nsd/nsconf.c'
patching file `nsd/nsconf.h'
patching file `nsd/nsd.h'
patching file `nsd/request.c'
patching file `nsd/serv.c'
patching file `nsd/tclcmds.c'
patching file `nslog/nslog.c'
patching file `nssock/sock.cpp'
patching file `nsunix/nsunix.c'
patching file `nsvhr/nsvhr.c'
patching file `nsvhr/nsvhr.html'
patching file `tcl/form.tcl'
[nsadmin@web aolserver]#
