# HG changeset patch # User Peter Mikkelsen # Date 1594917016 -7200 # Thu Jul 16 18:30:16 2020 +0200 # Node ID 830cd4a35ee93802a8263057c4dde4ab2202f91d # Parent 34a82bb15ad79d84345894707ac9bf0ebb43d9bc move stuff diff --git a/sites/pmikkelsen.com/plan9/basic_9p_server.md b/sites/pmikkelsen.com/plan9/basic_9p_server.md new file mode 100644 --- /dev/null +++ b/sites/pmikkelsen.com/plan9/basic_9p_server.md @@ -0,0 +1,58 @@ +## Writing a basic 9P server + +On plan 9 the entire system is build around the idea of namespaces +and that _"everything is a file"_. For this reason it is very easy to write +a new 9P fileserver in C since all the boring tasks are implemented in +libraries. This note describes a minimal program which serves a folder to +`/mnt/hello9p` containing a single synthetic file with the contents "Hello from 9P!". + +## The code + + #include + #include + #include + #include + #include <9p.h> + + void + fsread(Req *r) + { + readstr(r, "Hello from 9P!\n"); + respond(r, nil); + } + + Srv fs = { + .read = fsread, + }; + + void + main(void) + { + Tree *tree; + + tree = alloctree(nil, nil, DMDIR|0555, nil); + fs.tree = tree; + createfile(tree->root, "hello", nil, 0555, nil); + + postmountsrv(&fs, nil, "/mnt/hello9p", MREPL | MCREATE); + } + +## Explanation + +The global variable `fs` is a structure which contains function pointers +to all the 9P handlers, but since I only plan on reading from the file, +only the `read` field is set. The fsread function calls two helper functions +from the 9p(2) library which will create a response with the given string as +the file contents. + +In `main` I start by allocating a new file tree, since this 9P server deals with +a fileserver that has a tree structure, and therefore I don't have to worry +about how directories are handled for example. A file is added with `createfile` +to the root of the tree. + +The call to `postmountsrv` will mount the 9P server under `/mnt/hello9p`. + +## Thats it + +This is not very complicated, but see the manpages at 9p(2) and 9pfile(2) +and intro(5) for more information about the libraries and 9P itself. diff --git a/sites/pmikkelsen.com/plan9/network_booting.md b/sites/pmikkelsen.com/plan9/network_booting.md new file mode 100644 --- /dev/null +++ b/sites/pmikkelsen.com/plan9/network_booting.md @@ -0,0 +1,30 @@ +## Network booting into the server at pmikkelsen.com + +Sometimes it is nice to be able to connect directly to a remote server +from my laptop and have the same root filesystem available. +This is possible by typing `tls` at the boot prompt and then +typing `pmikkelsen.com` for the fs and auth server. + +## Speed + +On my internet connection some things can be very slow +(such as compiling the entire system), because of fs access now happens +over the network. The easy fix is to just start a cpu connection to the server +where the fs access can happen fast since it is on the same machine. This is +done by typing + + rcpu -h pmikkelsen.com + +Of course the server has a pretty slow cpu.. + +## Server settings + +Some steps are needed to make this work: + +1. The user must be added to the fileserver and auth server. +2. The fileserver must be listening for remote connections. +3. The correct ndb entries must be set (in the beginning I forgot `fs` and I could +only connect via tcp, not tls) + +More information about all those steps can be found in section 7 of [the 9front FQA](http://fqa.9front.org/fqa7.html). + diff --git a/sites/pmikkelsen.com/plan9/using_irc.md b/sites/pmikkelsen.com/plan9/using_irc.md new file mode 100644 --- /dev/null +++ b/sites/pmikkelsen.com/plan9/using_irc.md @@ -0,0 +1,37 @@ +# Using IRC on 9front + +While 9front comes with an irc client called `ircrc`, it can be quite annoying that it does not +keep a persistent connection. + +A different program `irc7` provides a server part which keeps a connection open to an irc server, +and a client part which allows for connecting to the server. This works great since it makes it possible to +get all the messages on a channel without being online all the time. + +## Setup + +Download the irc7 code via `hg`: + + hg clone https://code.9front.org/hg/irc7/ + +Build and install + + cd irc7 + mk install + +## Usage + +First the server program `ircsrv` must be started, so I would run + + ircsrv pmikkelsen irc.freenode.net + +to connect as `pmikkelsen` to freenode. After this (and maybe logging in), +it is possible to connect to different channels by opening new rio windows +and running + + irc -t '#cat-v' -b + +to connect to the cat-v channel. The `-b` option without any extra arguments +prints the entire conversation since the ircsrv was started, so it might not always be desirable. + +I run this on a remote cpu server that is rarely powered off, and then I just connect via +drawterm from linux to chat. \ No newline at end of file