Table of Contents
Installation
Step 1: Installing Lua
Your first step is to install a Lua engine. There are two ways to do this. The easiest is to use your distribution’s package manager. For example, on Debian-based systems you'd run a command along of:
$ sudo apt-get install liblua5.2-dev
The other way is to compile Lua yourself from a tarball. We'll see this briefly later.
Step 2: Installing MC’s build dependencies
If it’s the first time you compile MC on your system, you'll have to install some header files and utilities needed to compile MC.
If you're on a Debian-based system, you can do this by issuing:
$ sudo apt-get build-dep mc
Otherwise, if your system doesn’t have a similar command, you'll have to do it by hand.
Step 3: Downloading and preparing MC
Download from github:
$ git clone https://github.com/mooffie/mc.git
Switch to the Lua branch:
$ cd mc
$ git checkout luatip
Run ‘./autogen.sh’ to create the configure script:
$ ./autogen.sh
Everything is now ready for compilation!
Step 4: Enabling MC’s Lua support
By default the Lua support in MC is disabled. To enable it, add the
--with-lua option to configure’s invocation:
$ ./configure --with-lua
‘configure’ will then look for a Lua engine registered with pkg-config.
Optionally, you may want to install MC inside your home folder, instead of
overriding the system’s MC. To do so, use the --prefix options:
$ ./configure --prefix=$HOME/local --with-lua
When configure finishes, it prints a summary:
Configuration: Compiler: gcc -std=gnu99 Compiler flags: ... File system: Midnight Commander Virtual Filesystem cpio, tar, sfs, extfs, ftp, fish, luafs ... Internal editor: yes Diff viewer: yes Support for charset: yes Search type: glib-regexp Lua support: yes (Lua 5.2)
Pay attention to the last line, which in this case shows that everything went fine.
‘configure’ searches for Lua engines in this order: LuaJIT, Lua 5.3, Lua 5.2, Lua 5.1.
You may explicitly specify the engine to use using --with-lua=ENGINE,
where ENGINE is one of “luajit”, “lua5.3”, “lua5.2”, “lua5.1”:
$ ./configure --with-lua=lua5.1
In fact, ENGINE can be the name of any Lua library registered with pkg-config. Do:
$ pkg-config --list-all | grep lua
to see the available libraries. This is the first thing you'll want to do when trying to troubleshoot: this will tell you if a Lua engine is indeed installed, and whether your distribution uses some non-conventional name for it. (If your Lua isn’t registered with pkg-config, see the section Configuring without pkg-config.)
Step 5: Compiling and installing MC
Next, run make:
$ make
If it succeeds, install MC:
$ sudo make install
(You don’t need to use ‘sudo’ if you configured MC with a prefix residing inside your home folder, as demonstrated above.)
Configuring without pkg-config
Using --with-lua alone only works if your Lua engine is registered with
pkg-config. This may not be the case. For example, this isn’t the case
when you compile Lua yourself from the official tarball.
In such cases you need to explicitly tell configure the location of Lua’s header files and library. This is done using two variables:
- LUA_CFLAGS – flags to pass to the C preprocessor.
- LUA_LIBS – flags to pass to the linker.
Let’s see a complete example.
First, let’s download and compile Lua:
$ cd /home/mooffie
$ wget http://www.lua.org/ftp/lua-5.3.0.tar.gz
$ tar zxvf lua-5.3.0.tar.gz
$ cd lua-5.3.0
$ make linux
Make sure that you now have a liblua.a file in
/home/mooffie/lua-5.3.0/src.
(We don’t have to do make install here because in this example we'll be
compiling MC against Lua’s static library. Static libraries don’t need
to exist on a system once the executable using them has been created.)
Now, let’s configure MC:
$ cd /home/mooffie/mc
We'll build it in a separate folder to keep things tidier (but this is not mandatory):
$ mkdir build_lua && cd build_lua
Now:
$ ../configure --with-lua LUA_LIBS="-L/home/mooffie/lua-5.3.0/src -llua -lm -ldl" LUA_CFLAGS="-I/home/mooffie/lua-5.3.0/src"
…and, as before, pay attention to the last summary line ‘configure’ prints.
Finally, continue with make and make install, as demonstrated in step 5.
Troubleshooting
If the problem is in the ‘configure’ stage, check the output recorded in configure.log.
If the problem is in the ‘make’ stage, run it with make V=1 to see the commands actually issued.
Things to pay attention to when using the LUA_LIBS variable:
Do “-llua”. Do not do “-lliblua”, nor “-llua.a”, nor “-lliblua.a”.
When linking against the static Lua library, don’t forget to add “-lm” and (on Linux) “-ldl”.
Do not do “/path/to/liblua.a”. Break it down into “-L/path/to -llua” instead. Otherwise libtool gets confused and doesn’t add this library to the final link command (resulting in errors like “undefined reference to ‘luaL_newstate’”.)