How to install a package and resolve dependecies issues

I'm not using any packet manager in Slackware (I don't even know if there's one that can manage dependencies), so I have to install manually the packages I need. Sometimes this isn't so easy, because for running a program you often need other programs or libraries, and they aren't already installed.

So, let's see an example. let's suppose you want to install transmission, a light-weight BitTorrent client.

Step one: find and install a package 

This one is simple: if it's pre-compiled you can find it in your install CD/DVD, in the online Slackware mirrors (my advice is to search the package name in the list of packages, like this one) or on slacky.eu where you should search the package name in the right repository (in my case, 13.37 32bit). There it is:

First steps with Slackware: how to install software

When I started using Slackware, I was coming from Ubuntu. Used as I was to a packet managers doing everything automagically, I was a bit puzzled by Slackware's way. So after messing up for a while my first installation I discovered three ways to install software that I'm comfortable with:

• using a pre-compiled package (easier)
• using a slackbuild script (easy)
• using sources (less easy)

But let's start from the beginning.

Understanding how and where software files are stored

Usually in Slackware software is installed in /usr/, unless you specify otherwise. In most cases you will have all the software's files copied to /usr/lib/softwarename and a symlink in /usr/bin, usually linking the main executable placed in /usr/lib/softwarename.

Installing Mypaint 1.0.0 step-by-step

Mypaint is an amazing digital painting software for Linux, Windows and Mac. I absolutely love it, but installing it on Slackware 13.37 was a bit tricky...

First of all, download and extract mypaint 1.0.0:

wget http://download.gna.org/mypaint/mypaint-1.0.0.tar.bz2
tar -xvf mypaint-1.0.0.tar.bz2
cd  mypaint-1.0.0

Now, if you take a look at the readme file

cat README

you'll see that it needs scons to compile. If you haven't installed scons don't panic, there is an easy to get SlackBuild:

Alsa: multiple output, multiple sound cards, multiple users

I had some difficulties setting up alsa as I wanted, because I encountered some troubles:

• when more than one application was playing sound, the first one played nicely but the others wasn't playing at all, complaining about a "busy resource"
• solved this one, I had to setup the whole thing to work with two sound cards at the same time
• eventually, I wanted to enable concurrent sound for multiple users

Alsa Wiki's guides were useful only for a few things, but none of them gave me the whole solution. So after a deep digging, I ended up with this config:

pcm.USBmic {
    type hw
    card CNF8215
}

ctl.USBmic {
    type hw
    card CNF8215
}

pcm.internal {
    type hw
    card SB
}

ctl.internal {
    type hw
    card SB
}

pcm.wireless {
    type hw
    card Transceiver
}

ctl.wireless {
    type hw
    card Transceiver
}

pcm.internalDmixed {
   type dmix
   ipc_key 1024
   ipc_key_add_uid false
   ipc_perm 0666
   slave {
       pcm "internal"
       period_time 0
       period_size 2048
       channels 4
    }
    bindings {
       0 0
       1 1
       2 2
       3 3
    }
}

pcm.wirelessDmixed {
   type dmix
   ipc_key 2048
   ipc_key_add_uid false
   ipc_perm 0666
   slave {
       pcm "wireless"
       period_time 0
       period_size 2048
       channels 2
    }
    bindings {
       0 0
       1 1
    }
}

pcm.both {
    type route;
    slave.pcm {
        type multi;
        slaves.a.pcm "wirelessDmixed";
        slaves.b.pcm "internalDmixed";
        slaves.a.channels 2;
        slaves.b.channels 4;
        bindings.0.slave a;
        bindings.0.channel 0;
        bindings.1.slave a;
        bindings.1.channel 1;
      
        bindings.2.slave b;
        bindings.2.channel 0;
        bindings.3.slave b;
        bindings.3.channel 1;
        bindings.4.slave b;
        bindings.4.channel 2;
        bindings.5.slave b;
        bindings.5.channel 3;
    }
  
    ttable.0.0 1;
    ttable.1.1 1;
  
    ttable.0.2 1;
    ttable.1.3 1;
    ttable.2.4 1;
    ttable.3.5 1;
}

pcm.!default {
        type plug
        slave {
                pcm both
        }
}

ctl.!default {
        type hw
        card SB
}

How does this strange thing work? Let's look at it step by step:

Why Slackware and why this blog?

Slackware because it's:

• lightweight
• stable
• highly configurable
  
• hard to understand, which is useful to learn how to use linux. :)

At the moment I'm using 13.37, the last version, by the advice of Davide Bianchi (and if you never heard of him, go read the Tales from the Machine Room).

Why this blog? Because sometimes I discover a nice solution for a problem which is hard to find online, or I write a useful script, and a blog is a nice way to keep a handbook always accessible, from anywhere and by anyone. So let's cut the chatter and begin with the useful stuff! :)