hpr-knowledge-base/hpr_transcripts/hpr0801.txt

Episode: 801
Title: HPR0801: Slackbuilds
Source: https://hub.hackerpublicradio.org/ccdn.php?filename=/eps/hpr0801/hpr0801.mp3
Transcribed: 2025-10-08 02:45:17

---

Hi everyone, welcome to Hacker Public Radio. My name is Klatsu. I have a three-part series
for you this time on packaging, actually, packaging code for Linux and BSD. So I'm not
a package maintainer. Really, I'm very, very novice at it, but I don't really hear. I've
never actually heard an episode on the subject, and I maintain a couple of packages over at
slackbuilds.org, and I built an RPM, and I built a port once. So very, very much a novice,
but in this episode I'm going to discuss slack builds. And I'm going to discuss slack builds
first, because I don't know necessarily that it was a terribly early development. I don't know
when this was all devised. I don't know the history of really any packaging formats, but I figured
it was a really good one to start with, because it is, in my opinion, the simplest to understand
that the most straightforward one of them. It's the one that I kind of started with first. So,
packaging Linux applications, of course, is a pretty important task, I think. I mean,
one of the selling points, I think, maybe not at first, but one of those things that becomes
very, very addictive and very, very almost expected at this point, is that when you are using Linux
that at some point you start to just kind of expect naturally that application that you just
heard about from someone, naturally that will be in your repository. It's just kind of a given.
So, I wanted to encourage people to look into packaging, because it's a pretty cool little trick
to know, and it can be very helpful to other people as well, because if there's an application out
there that hasn't been packaged for your favorite distribution, or that's maybe lagging a little
bit behind the curve, then you might be the person to pick that up. So, we'll get started with
slack building. Now, of course, I'm fully aware that not everyone's going to jump out of their
chair at the end of this episode, and go package stuff for slackware. But it really is a very
beautiful packaging format, the slackware packaging, because it doesn't use anything specific to slackware.
Well, it does, but it doesn't. The slackware packaging format is a shell script, and the shell
script goes through the code that you want to compile, and it sets up a little destination directory,
sort of a temporary directory, where everything is going to be compiled, and then installed into
that temporary directory. A couple of other files in the package, we'll get into that later, but
at the basis, there's this little shell script. It's the slack build itself, a shell script, and it
compiles the code, puts everything into this directory. Now, if you look at this directory, inside the
directory, there is, if you go into that directory, you would almost think you were inside of your
computer, because you'll see really familiar folders, like, slash usr, and slash etsy, and you'll
think, gee, what's in there? So you go into slash usr, and look at that, there's a slash bin,
going to slash bin, and there's the program that you were compiling, the binary for that program.
Back out of there, go into the etsy directory, maybe, and maybe there's another folder in there,
or maybe not, but there's a dot-conf file for the application that you're compiling, and then maybe
you go back out, and there's a slash usr, slash share, slash doc, and then there's the documentation.
So basically, this little destination directory is a little tiny clone of a Linux system,
without anything in it, except the application that you want to compile. So you've just taken
source code, you've compiled it into its own little folder. It's completely bundled up in this
one folder with lots of subfolders that correspond exactly to a Linux system, so that if you,
specifically, do a Slack system, but that's pretty universal. So if you overlay that directory onto
a Linux system, then suddenly you've installed that application, makes sense, right? So in theory,
of course, you could go through, and you could give that folder to people, you could zip it up,
and give it to people, and they could unzip it, and they could move everything that you've compiled.
If it was compiled for their architecture and everything, they could move everything that was
compiled onto their computer in the corresponding places, meaning if it's this destination directory,
they see a U.S. slash U.S. R slash bin slash whatever, then they'll take that whatever, and they'll
put it in slash U.S. R slash bin slash whatever, and then they would go into the slash U.S. R slash
share slash dock, and they would take all the documentation and drop it into their own slash
U.S. R slash share slash documentation. And the same thing for the Etsy config file, they would take
the, they would take it out of the Etsy folder in their little destination directory, and they'd
put it into their own computer's Etsy folder. And if you think about it, that's all installing
software is, right? There's nothing really magical going on there. Now the one thing that is a
little bit magical, or it might seem that way, is that there are dependencies. There's code on the
computer that when you're building that application, it kind of wants to see that code, it wants to
build against that code. If the user doesn't have that code on their computer when they're compiling
the code, then that application isn't going to be able to compile. And that of course is a dependency,
that's what that's all about. So for this reason, slash building is kind of one of the easier
packaging formats because it doesn't do dependency resolution. It doesn't do any kind of checking.
It simply runs the dot slash configure or whatever option that particular brand of compiling takes.
It's usually a dot slash configure. And if the dot slash configured check fails, then it cannot
proceed to actually make the program. So the burden is on the user, the slackware user, to resolve
their own dependencies. So enough talk. Let's just go ahead and build something. And the program that
I've chosen to build in all three of these demonstrations in each episode is the little program called
Yes, Please. Yes, please is a little C application, I think, by Sigflup. You remember Sigflup of
Hacker Public Radio. She's a great programmer type person. And she came up with this Yes, Please
program that will take a screenshot of your computer screen of your desktop. And then it will
automatically upload it to the fine website, UnixPorn.com. Now UnixPorn, of course, is not porn,
it's Unix. And it's a place where people can post their desktops, just whatever they're looking at,
you know, during the day on their Linux machine or BSD or whatever, Solaris, whatever. And they can
post it on there, then everyone gets to see, you know, how they have their computer set up. So it's
just gratuitous screenshots, basically. So you need an account over at UnixPorn. It's a free
account. It's just like me and the last name God and Cobra 2, it admin the thing. Oh, and I think
330 technically, we're admitting the thing. And you can just use Yes, Please to upload to it
straight from the command line. It's a really slick little application and it's got just enough
complexity, I think, to make it not a completely easy script to write, you know, a package to write,
but it's at the same time it is very simple because it's a very small application. So let's take a
look at it. The Yes, Please source is currently at least the one that I've built packages for is
Yes, Please underscore, underscore four, that's August and August, underscore four, underscore
twenty ten dot TGZ. That's the source file that that SIGFLOB distributes. That's the source code
and everything in there. So for a Slack build, what you would do is you would grab that source.
Well, actually, I should start out by saying this is going to be common on all three packaging
formats that are all three that I'm going to cover. Sorry, I didn't mean to imply that they were
the only three packaging formats. If you think that those are the only three packaging formats,
go listen to HPR episode seven thirty three by Marcos where he talks about just how many
packaging formats there really are, but I'm doing Slack builds RPM and port because those are the ones
that I learned and that's why I'm doing them. I mean, Slack builds and RPMs, I actually use a lot.
Port was kind of fun and the other ones I just I haven't gotten around to really looking into
them. So for any package that you're going to be doing, it's a good idea to have kind of an
environment, like a building environment setup, as well as a clean install setup. Those are two
tall-ish orders because if you're lazy, you won't want to do them, but it is important to do them.
Especially for something like RPM, which apparently was traditionally at one point kind of done by
root because it had a lot of, you know, it was, it was the RPM builds were done outside of the
home folder and stuff like that and people kind of decided, you know, that's really crazy to be
just sitting in root all day while you're packaging this thing up. And yeah, it's probably true,
it does seem pretty crazy. So it's a good idea to kind of make your own packaging identity.
And I mean, I always have two users, at least two users on every computer I have. My everyday
normal computer usage and then a another account just kind of just they're hanging out because I
like to have multi-users just because I like to explore what what interesting things happen when
you have two users, even though they're both me. But so if you can do an ad user or a user ad,
whatever you've got on your system and just create a new user for yourself who will be your
packaging identity, that's not a bad idea. Now at the same time, before you go doing doing that,
another way about that, and this isn't a bad way, believe me, is to just grab Qemu,
Qemu, however you say that, the virtualizer and grab the latest distribution of your
distribution and fire up an instance of Qemu and do a little install of that. Qemu, I've done either
a hacker bullet radio episode on it or I've done a bin rev blog, which is also now sort of mirrored
over on my go for space point go for like in links or in Firefox go for colon slash slash slacker
media dot info colon 70 and you'll find a link to my go for space from from there. So you can look up
the Qemu tutorial on in my articles and it's a really simple one. I like using Qemu because it's
just it's fast and it's easy. You don't have to worry about installing a whole virtual machine
client, you know like virtual box or anything or vert manager or anything like that. You can just
fire up a quick instance of Qemu, Qemu make a make a disk image and then install your your
distribution on there. Do a minimal install possibly and and you're you're good to go. You don't
even need X for I mean it's really this is all going to be on the command line so you can just
install a really simple version of your of the distribution that you're packaging for and it really
is quite important to do this in a virtual machine because I cannot tell you how many times before
I really really understood packaging, not to say that I really really understand it now but I
certainly understand a better than I did when I was first starting out but I can't tell you how
many times I would write a slack build on my machine for it is swearing that I've got a fairly clean
machine and and of course there'll be something that I just I forgot that I had installed a hugely
major dependency of this application and I just never noticed that it's there because I've already
got it on my computer whereas if it was a clean install a completely clean install and I was packaging
the thing I would have known right away that when I did the dot slash configure oops it didn't work
because you know such and such was missing so it's very important to have a really really clean
install so that you're building against what you really kind of have to assume everyone else is
going to be building against you have to assume that they're starting from a from from ground zero
from the ground up from their distribution okay so that's very important it's all free it's very
easy to get started the next thing I guess would be if you're not familiar with compiling software
if you're not completely familiar with compiling software I did an episode on that over on
new world order for sure so that's augcastplanet.org slash canoe world order I don't remember the
episode number but it's an episode completely about compiling software so if you're not familiar
with it and you feel like I'm rushing through parts in this episode you can either go listen to that
and yes please like I say is a really good little application to practice on too so if you haven't
compiled that often and you want just sort of practice yes please is great because there's a couple
of little dependencies and then you can resolve those and suddenly you're building and it works
and and everything's great okay so we've grabbed the yes please source from the from the homepage
and you know honestly the easiest way to get there the the way that I get there is I simply go to
slackbuilds.org because I mean heck that's what we're doing anyway and you can even grab the slack
build if you want to kind of follow along as it were so if you go to slackbuilds.org down at the
bottom of well at the top of the page there's a search box and it'll be set by default to 13.37
so just put in the word yes please and that is yesplz and then hit return and it'll take you
to the yes please slackbuild and you'll see a read me with some asky art that doesn't quite
translate very well to to html unfortunately and then you'll see a source download with the MD5
sum next to it you can download that to your computer and then right underneath that you'll see
download slack build and that's that's going to be yes please dot tar dot gz and that is uh
signed gpg sign so you can verify it that and uh then you should have in your little packaging
identity wherever that is whether it's on a virtual machine I make a directory called slackbuilding
and I put the source and the the slack build template that I'm going to use uh which slackbuilds.org
actually even provides so in terms of getting it to work it's a great starting point okay so I'm
going to just untar this yes please dot tar dot gz so that's the slack build itself not not the
source code just the the actual slack build like I've said there are about well there are about
there are either four or five essential files in a slack build again this will be really similar
in rpm and everything like that it's they've typically got a pre standard format and they're
actually more similar than they are not in in many ways so um the the first file is the easy
one that's the read me those are always good to have I tend to be very I tend to try to be very
verbose in my read me I never want to assume that someone's coming to slack builds and getting
yes please because they know everything and they're doing it all from the command line in one command
that's just you know I like to try to assume that people are going to need a read me if they're
reading the read me they probably want the information at the same time I don't want to go on and on
either I want to kind of be informative up at the top and then kind of break it down for people
down at the bottom having said that the yes please read me is marvelously useless I should probably
work on that but usually my read me's are quite helpful but the read me there's no format there's
no requirement the read me is a read me it's it's something that you can talk to the user
through and kind of help them do whatever you think that they need to do in order to get that
thing installed okay so the next one is a little bit more specific actually quite specific it's
called the slack slack slack dash description really but it's dash d e s c and it's very very
specific about what you must do it has a handy little ruler at the top which is a bunch of dashes
it's got the application name down the left side of the document and then it's got play a place
for text so it's about I think it's probably about 80 characters wide I would imagine or 79 or so
within that handy ruler and then you've got 11 lines to use so you can say whatever you need to say
in that 11 lines but you have to be careful not to go over that or go outside of that that
ruler because what they're going to do is crop all that junk off and and show the contents of
the slack description within the little package management tools that slackware ships with by default
so you have to follow the format here and of course in any packaging format you're going to find
that there's files that are very specific obviously because it's all scripted right I mean
so they need everything to be exactly the same all the time so traditionally in the slack description
you place the title at the top of the of the description of the 11 lines of description then
you give like a brief description of what exactly this is so that when people are kind of just
browsing through the packages they'll see oh yes please the sigflux unix porn.com CLI screenshot
and upload tool okay I get it that sounds interesting I'll download that and then typically it's
very handy at the bottom of your description to either have like a link to the home page of
that software so that they can go check it out if they want to but also definitely have what
dependencies are required so I simply write this requires for instance in this case lib jpeg x11
and p threads now in this case happily because it's slackware all of those are included in a stock
slackware install so the user actually doesn't have to go out and resolve any dependencies they can
simply go to yes please they can they can do the the install script and and that's it that's the
end they don't have to do anything so like I said yes please is kind of easy and yet it's kind of
complex just complex enough were this a non-standard stock slackware install for instance maybe this
person is a pro they've been using slackware a lot they know that they never use jpegs so they
just didn't even bother installing lib jpeg or maybe even more realistically they they don't
really use excellent let's just say that they don't have some one of those dependencies when they
read that they'll say oh gee I guess lib jpeg is actually required for this I better go install
that and then they can pull that package down from from the slackware server and install that and
then they can install yes please so it's manual dependency resolution it's a beautiful thing
because you actually know what's going into your computer and you actually get to compile it
the way that you want to if if it's that important to you but I digress so that's the slack dash
dc or description file the third file that one would do is the yes please dot info file the dot info
file is again very structured very specific as to how it needs to be structured and this you're
going to you're going to really well I mean again once you see all these packaging formats it's
going to all kind of start to look really really familiar to each other so that's kind of kind
of neat so um the yes please dot info file starts with a program name or PRG and AM and that equals
in this case quote yes please end quote next line is version this is tricky with sigflux yes please
because she didn't follow any kind of uh established at least that I know over that I can tell
an established method of naming her program so the version in this case is AUG underscore four
underscore 2010 now more traditionally like if you read up on packaging and you go to like fedora
documentation and read up on how to do RPMs or the bsd packages uh porter's handbook then you'll
you'll read up and they kind of have like this thing about you should follow this convention it's not
law or anything like that but it's a convention and that is that you have your program name and then a
dash and then your version number and then the compression and that's just kind of how it's done
fairly universally I've found in my very limited experience as a big famous package maintainer
with all my like three or four packages that I have so uh sigflux flew in the face of that convention
and and just named it the month and the day and the year that she she actually released that
version of it on and and at first I didn't really see a problem with that until I started building
packages for it and it seems like every packaging the language as it were or convention out there
demands something completely different but that's that's okay that's what makes this one a little
bit fun so in this case we're just doing the whole string as the version homepage is uberlead hacker
force dot deep geek dot us and then the download equals hgtp colon slash slash hobones dot dog soft
dot net slash yes please underscore aug underscore four underscore twenty ten dot t gz so that's all
the information so far that that the that like someone like you or me if we just have the slack build
we could look at that file right there and figure out where to go to read up more about the application
and even the direct link to these to the source code for which this slack build is created MD5 sum
self explanatory uh and then there's a separate download link and a separate MD5 sum for an x86
underscore 64 version that is obviously only to be used if these are binary packages that were
installing uh but we're compiling from source here so there is no separate download for x86 64
so we don't need to fill that in we can leave those empty just two empty quotes maintainer is oh
look there's my name uh the email clatoon at um member dot fs f dot org and then approved by my
friend and fellow slackware and slack build user decimero who I actually interviewed at
southeast linux fest but the recorder wasn't really on the right way so it didn't quite work
okay so now finally finally we get into the actual build script itself and this is uh yes please
dot slack build and once again there's that convention you have to do the the the name of the
application and you know capitalization and everything like that it counts so it's yes please
dot slack build where the s and the b are both capitalized that's how it's done you don't want to
deviate from that so like I say slack builds they come with some great templates and if you go to
the get repository of slack builds they have even I mean they've got some good templates on the website
slack builds dot org if you go to their get repository they have templates for everything for
pearl applications for automake applications which is which this is uh for seemake stuff for
java stuff it's just got all kinds of templates which are really really helpful but generally speaking
the I mean obviously I'm not going to just read this line by line so if you want to if you want
to go get the package the slack build package and then read through the code yourself that would be
a good idea most of this is not even my code um this was a really a pretty simple slack build so
a lot of this is basically just robby workman and and and decimero and and um all the guys over at
slack builds it's just kind of their their scripts that everyone else gets to kind of modify and tweak
and leach off of and makes you feel really good about yourself because you wrote a slack build
when really you did like you know ten percent of the work but that's ten important
percent okay so the program name reiterated here in the script because we need the variable uh
is yes please the version org underscore four underscore twenty ten the build is dollar sign curly
bracket build colon dash one uh curly bracket and that's what that is going to do is append a dash
one to the end of the script like after we've built everything it's going to have a dash one to show
that this is build build one um and then a tag and the tag is an underscore SBO so all the slack build
files all the packages that you build via slack builds will have that tag underscore SBO if you
go and download a slack build from say alien bob's website who beets a lot of cool packages uh
then he'll have an underscore alien tag for my personal packages that I I build for myself but
I don't submit the slack builds for whatever reason which isn't all that common to be honest but there
are some things where I know that the slack build already exists but I don't want to submit uh I don't
want to use their slack build so I'll modify it heavily or I'll just do my own version and then I'll
have it on my computer so I'll have the underscore class too so you can tag your files just to kind
of differentiate where these packages came from notice here as well that we're using variables
right here at the top of the script that's such a great habit to get into because then you don't
have to you know you you you establish your variables right up at the top and then you don't have
to go through the script and like do a said replace or anything like that you know it well you know
said um you don't have to replace stuff because you only list it once at the very top of the script so
if if sigflup comes out with a really cool new version of yes please on august 8th 2011 you don't
have to go through and change that everywhere you just simply go into your slack build file you
change the version you close it and you build it and suddenly you've just updated your slack build
so this is very very efficient and of course I'm marveling over it but it's probably like
something that programmers have done for for years and years and years I think it's really smart
though the next chunk of code I'm not going to read through but it's basically and well it is
it's an if statement with a little case loopy thing in it and it's establishing the architecture
of the machine and it's done really really well this is like just cool good old fashioned
bash parsing kind of stuff where you you simply tell it to do a you name dash m and if the value
returned from you name dash m is for instance i 486 or i i something 86 then we set the architecture
as i 486 if it is arm then we set the architecture or arch ARCH to arm and if it is anything then we set
the architecture to whatever that value is so it's a really cool kind of auto detection kind of
technique I have taken that chunk of code right there simple that may be probably I've taken that
and just used it on so many different things so many little bash scripts that I've written where I
just want to get a value and then examine it and and set some other variable to whatever that
returned that's it right there it's it's just it's done for you just go get the template and rip
off the code it's really cool okay so then we set some more variables and this is kind of cool
because we most importantly we set a temporary directory to slash temp slash sbo we set a package
to something inside of that temporary directory slash package dash program name so meaning
that as we build this package or as slack builds you know the automated script as it builds this
package it's going to put everything into slash temp slash sbo slash package dash program name so
in this case it'll be package dash yes please so this is good to know because if if you were
packaging and it fails a few times you can go to slash temp slash sbo slash package dash you
yes please and look inside of there and see what did you know how far did it get what what's going
on inside of that package that we're trying to form and then the output is set to slash temp then
we go through and set some compiling like some make flags basically and it does this based on
that variable that we established just a minute ago where we did the you name dash m so we did
new dot new name dash m and whatever that returned and if you don't know what you name dash m does
open up a terminal right now and type in you name dash is space dash m and you will see that
it actually gives you the exact architecture of your machine so in this case it's x86 underscore 64
on the computer that I'm using right now so we did a you name dash m we got some value and then
we took that value and set the variable arch ARCH equals you know whatever value we got back from
you name dash m so in this chunk of code we're saying okay so if the value of arch equals i
486 then slkc flags equals quote negative oh two space dash m arch equals a 486 space dash m tune
equals i 686 closed quote libder suffix is nothing because it's a 32-bit system there when you go
a libder like slash usr slash lib or slash lib it's just slash lib that would be as opposed to
for instance a couple of lines down where it says else if the value of arch equals x86 underscore 64
then slkc flags equals dash zero to space dash f pick and the libder suffix equals 64 so this is
very important stuff because it's looking at the architecture of your computer and setting some
pretty common little flags that you you want to maybe keep in mind when you're compiling software
and then we do a set space dash e the set space dash e means that we're going to exit the script
if there are errors this is such a great great thing and I never really understood why it was done
in slack builds I always kept it in because it was in the template I didn't have a deep understanding
of why it was done and then I started doing a lot more scripting at my job and I would run a script
and it would run through the whole script and then I'd look at the results and it turns out that
half of the script didn't actually get done and I would always think to myself why did it
continue going if if it couldn't even find that directory you know and just kept kept working but
it it was missing like half of the things that I asked it to do well it turns out that I had never
said it to to stop there was no there was no warning that hey if you encounter errors then bail
so set space dash e will help with that sort of thing rm space dash rf space dollar sign package
why would we do that well think about it if you're if you're building the package and you're trying
to build it and it fails so then you try again well you don't want to try to build the package into
itself right you don't or have some kind of conflict where it says directory already exists
so as part of a fairly early step in this process is to look and see if an existing dollar sign pkg
exists and if it does remove it recursively and forcefully the forcefully flag of course is set
because otherwise it might if if we have rm set to um rm dash i then it would ask us hey are you
sure you want to remove this and we don't want that we want our script to run very very silently
so rm dash rf dollar sign package and then we make some directories we make a directory
called dollar sign temp dollar sign package and dollar sign output and you'll remember of course
that those are variables that we set earlier in the script temp was set to slash temp slash sbo
package was set to being in the the temporary directory slash package dash yes please or
really program name but in this case yes please and then output was set to slash tmp you'll
notice that there's a dash p flag after the maker and what that stands for what that means is
to make any necessary parent directories turns out that this is a really handy trick to know because
if you're ever making a number of folders like you want to make a i don't know directory of a bunch
of skinny puppy albums so you'd say make your skinny puppy and then you'd have to go into skinny
puppy and then you'd say make their vivisect and then you'd say make their um maybe inside of that
you'd you'd have the the remixes and the normal ones you know if you wanted to do that you could
just do it with one command by saying make all the parent directories that are needed so you could
say make your dash p skinny puppy slash vivisect slash vivisect live and then again for the whatever
but the point is that you can actually it will make everything leading up to that directory for
you you don't have to actually do it in separate commands it's quite nice um that was way over
complex for a very simple explanation uh so then you cd into slash into uh temp you're sending
the shell script you know the the executor of the shell script into the temporary directory
this can get complex because you have to remember where these commands are being executed from
this is something i try to actually avoid in my own shell scripts because i always get confused
happily a lot of this is pre scripted in the slack build so you don't have to really keep track
of it as much if it's a simple compile it's not always that simple so sometimes it does become
tricky and again you do an rm dash rf of the program and the version just in case it's already
in progress if it's being built in that temp directory and then you untar and un gzip or whatever
needs to be done that program version so this is the source code that the user will have downloaded
on their own and placed in that directory and it's going to need to untar it now that's a line
that obviously you're going to have to change if your source code was tar.gz or tar.bz2 or
.zip whatever it might be that's kind of a line that you're going to have to keep an eye on if you're
building a lot of slack builds from from a template file uh and then notice that we cd into that
program version and we change the permissions this is again something that's going to be fairly
constant in the packaging stuff where you have to keep in mind that we're building and distributing
on linux and and unixy systems so permissions actually are going to matter the next chunk of code we
we do what we basically do the we set the c flags for the for the comp the the compilation
process and we do a dot flashed in figure with all of the associated options that you may or may
not want to have and this is kind of an important thing at least to me uh it it helps you keep everything
very consistent and it helps you make sure that everything actually works but things like setting
the prefix or setting the what what library directory you want to refer to where your configuration
files are kept and some programs like you know the more complex programs like ffnpeg I mean there's
a million different options can drink configuration that you can pass so uh audacity too there's
a bunch of different ones so sometimes you'll see a list of configuration options that just take up
well your whole screen really I mean it can be very complex so that's a very important part and
the only way to find that out and really the only I think the only way to do a slack build
properly is to go through the actual source code and run through the compile the the compilation
process a couple of times so if we go to the source directory with if we um we untar it
ungeezip it and go into it and just do a dot slash configure dash dash options or dash dash
help I'm not sure it it seems to depend on unlike the uh on the program itself I've seen both I
don't know what the uh the deciding factor on that is but the dot slash configure dash dash help
will show you a full list of all the potential configuration options that you can pass to the
dot slash configure process so in this case it's it's it's still a screen full I mean it's a pretty
it's it's I've never really seen one of these it's just a couple of lines but if you read through it
there's some really important stuff you know it's just kind of some of the stuff you don't even
have to set because there are defaults and it tells you what the defaults are for instance the
mander wherever the man file is going to go dash dash man dir equals some dir and then it says
well in square bracket graph square brackets that is prefix slash man well what is prefix
we'll go up a little bit to where the dot slash configure option tells us what the prefix is
and it says okay the prefix is dash dash prefix equals prefix and the default is slash usr slash
local and that's actually kind of funny I don't think I don't remember noticing that before
I actually like usr slash local as my as my default prefix but I I don't know that that's
always the prefix that it's usually just slash usr it seems like a lot of distributions and things
are going away from the slash local folder but yeah that's always interesting to look at but
anyway the the dash dash man dir obviously would not be something that we would need to specify
if if the default was something that we were perfectly happy with but if you want to override
that then you certainly can do that as well and in fact it looks like in this script we do override
a prefix we have dash dash prefix equals slash usr so it's not going to be slash usr slash local
it's just slash usr and that is to keep it consistent with the rest of slackware of course if
if for some reason you felt like it doesn't belong in slash usr slash whatever like slash bin
or slash share slash man whatever or slash share slash man whatever path is going to kind of
cascade down from different components of what you're compiling and installing you could
always change that prefix and it's done it's done sometimes on on particularly large or maybe
somewhat intrusive applications you'll see things that installed themselves to slash opt slash
local slash bin or to slash usr slash local slash bin whatever one of those two sort of classic
this was installed by a third party or you know not a default system kind of application
so for for us though we're just going to do a simple slash usr to be nice and consistent with
the rest of slackware then we do a yes a make yes please and you can see that I did a comment in
there that says make install is broken and installs the file to the build system now this is
funny I wish I'd read this note to myself a long time ago actually because I think I when I
built it I obviously knew that then when I was doing the RPM of yes please I ran into that same
problem and spent like a day trying to fix it and I'm just actually just now seeing again my own
note to myself in here but yeah so sigflup used an install script that her I think her make file
refers to the install script it it runs that install script and that install script gets some kind
of option from you know the environment that you're in and and so far on at least two of the
systems that I've built a package for I know it happened on slack build and I know it happened
on RPM that install script just didn't quite didn't match up with with the the packaging that
that I was doing I could be doing something wrong but but that's that's what I found so we do
simply make yes please and then we do an install dash d dash m 0 755 dash s and then dollar sign
program name space dollar sign package slash us slash bin slash program name so what we're doing
there is very very explicitly telling the install where to put the binary that it's about to compile
so the make command when we said make yes please what we're doing there is calling out a very
specific option in sigflup's make file so if you go back to her source code that we just
unzip to look at the configure options if we go into her make file well you won't see a make file
unless you did the configure but you will see a let a make file dash dot i in if you do a less on
that or cat or more whatever you prefer then you will see that on the left side of the the make
file there are words and then series of commands after them so you've got like I'm I'm looking
down under all the c flags and prefixes and stuff you see yes please and that's simply doing one
thing and then you see an install so if we'd said make install what would have happened was yes please
jamaud plus x dot slash install dot s h and then dot slash install dot s h s please to the prefix
to the bin to yes please so it's kind of hard coded in her make file to do a certain set of commands
that we actually don't want to do so we simply want to make the binary we don't want to install it
at least not the way that she is installing it and then on the separate line in our own script we
said install dash d space dash in whatever and then we said here's where we want you to put the
the binary which of course isn't in our system we're not really installing yes please we're installing
it into that fake little clone that destination directory that we've created and where is that
directory do you remember look up in the script you'll see it yes exactly it's in slash temp slash
s b o and then of course it's slash package dash yes please so that's where we're actually installing
everything so if you if you think about it when all we're doing is a normal everyday source code
compile but every step of the way where something's actually getting compiled we're redirecting all
of the output to the fake system with this fake slash usr slash bin and a fake slash usr slash
share slash dock and a fake slash Etsy and and all these other in a slash a fake slash lib so
that's that's all that's happening in a package you're you're you're you're building and putting
it into one location that isn't your system because you don't want to put it into your system yet
you want to put a new package that you can then distribute among your friends or you can say okay
computer now I want you to overlay this package onto your file system so that of course later on
when you get tired of that application or when you want to upgrade it you can very cleanly
how you have a record of everything that you've just done and you can uninstall or you can upgrade
without going through jumping through hoops and that's I mean that's what packaging is all about
right that's why people keep applications and packages and don't just keep installing everything
straight out of source code all right so we've got a package that we've installed now there's not a
whole lot of documentation with sick of flops application but there is a read me file and it is
it it seems to be a convention of of all the packaging stuff that I've seen so far again all
well three of them that I've actually looked at that if there is documentation then basically you
I mean even if it's not like a man page or something then you're going to keep track of it you're
going to install that onto the system as well as considered part of the application so in this
case we are going to make a directory without dash p flag again you remember how I explained
that that makes all the parent directories and we'll put that into of course our package so that's
the package the dollar sign pkg variable and then just like I said this in we're going to put it into
slash usr slash doc slash program dash dollar sign version I kept saying slash user slash share
slash doc I guess it's just slash user slash doc and then we're going to copy all of the documentation
over there which in this case is all of one file so you copy cp dash a that makes sure that you
get everything recursively and maintains all the different permissions and stuff like that I think
and then we've got a little slash but we're really we're just saying copy the read me file to that
one destination that we've just made which is the slash usr slash doc slash program version which
of course isn't the real one it's the one in our destination directory our package and then we
we we we cat the slack build itself into that folder as well into that directory as well why copy
when you can cat and why cat when you can copy it's kind of like in the slack book if you've ever
read that or if you're ever going to go read that they've got like in the same kernel compile lesson
they've got like two or three different ways of copying a file and there's like literally line
after line it's just like why did they copy that and cat that and to this day I don't know but you
know it's it's helpful to to kind of see all the different ways you can do things um and finally
we're going to make a make der dash p in the package slash install and into that install folder we
are going to cat from the current directory the slack where the slack dash description file and now
if there was a man page that was built for this and there isn't there's a yes please space dash
dash help but that's not a file that's part of the program itself so there is no man page so we're
not going to do anything with man pages this had no pearl or or um you know this didn't have
anything else involved so there's no meta little hidden things to strip out or get rid of so again
this is a pretty simple build comparatively but at this point we could do all kinds of cleanup
and again you're going to see this in the other packages where the after you've installed it
you you want to kind of clean up after yourself and make sure that you're not leaving a whole
bunch of bits and pieces lying around for for your user to have to clean up on their own tidy up
a little bit and after that you see the into the package and you issue what is a distinctive slack
where application called make pkg and that is it resides in slash s bin slash slash make pkg and so
we're basically converting everything in this directory that has the exact correct structure and
skeletal form of a slack package and it's it's taking all that stuff and putting it into well
really just a tar g zipped archive so make package make pkg while I say it is specific to slackware
it actually isn't specific to slackware at all because if you do a less on slash s bin slash
make pkg you will see the shell script and all the code or you know you'll you'll see the
the application right there and it's just a bunch of unique stuff it's it's normal every day
bash kind of shell kind of stuff that anyone could do so this is a really really I just can't
get over how like beautiful this this format is because it is just it's pure
unix it's just a bunch of shell scripting and it's just so effective why is it so effective
well before we go into that we should run the script and see what actually happens so the way
that you run a slackware script or a slack build script rather is that you've got your folder you've
got your little slack build folder with our for obligatory slack build files in it and you place the
source code package all zipped up and everything just like you got it from the internet you place
that inside of that folder you chamod the slack build script to be executable so that's chamod plus x
yes please dot slack build and then become root su into your root password and then run the script
dot slash yes please dot slack build and that finds this source package sitting next to it it
unzips it it moves it over into the temporary directory and builds it and compiles it and all
that other stuff that we've just written down in the script let's look and slash tmp and we'll
see our newly built yes please underscore august for twenty ten dot tgz well underscore x86 64 dash
one underscore sbo dot tgz and that is of course a normal everyday slack package that we could then
use install pkg to install onto our system and it it's simply unarchives that directory and takes
every all those little bits and pieces and dumps them into your file system where they belong and
spits out like a little description for you and stuff like that and it is truly as simple as that
the really cool thing is that if you ever want to look and see what has been installed on your
system in the lifespan of your slackware system you can simply do a ls on slash vars slash log
slash packages and there they are all the packages that you've ever installed now those aren't
the they don't contain the binaries and everything you know there's no reason to keep that stuff
around but they they do have it is a list of of everything that was installed and those each of
those packages contains a file list of everything that was installed and that's not just for your
information of course because if you ever went to go do a remove pkg then the system could look
at the file with all of the little folders and directories that it lists as having been part of
that install and it can see if they're unique you know make sure that they're not being used by any
other package on your system and if they are unique then it will remove that file from your system
and that's how remove pkg works so the install pkg takes your slack build and overlays it over your
your file system and records exactly what it has done in a plain text file in your slash vars slash
log slash packages and the remove pkg caps that log file and does a unique or sort with unique
flag probably over everything else figures out what it can and cannot remove and then removes it
and you're done it's that simple it's that generic notice how there's no complex packaging front
end there's no database underlying all of this it's just shell scripts plain text traditional
unix commands very very very cool and it's easy enough that someone like me and you dear listener
can actually start with on your own you know I mean if you know how to shell script you you
basically know how to make a slack build slack slack builds that that format that that packaging
format is the one I mean that is what is used by pat vulcarding to make slackware so it's a very
it's all very cohesive and very tried and tested so very robust little packaging format very simple
and I think once you do it or even once you've listened along to me doing that it does help you
understand what's going on during packaging because while this is very well I keep saying it's
non-specific but this is something that slackware does it's it's it's all the same idea it's
it's packaging so when we do rpm on the next episode a lot of that is going to sound very
familiar to this one and I do hope that you'll return for that episode on rpms but for now I
think we're finished with slack building I hope you enjoyed this I know it's been a long episode
hope it's been informative thanks for listening
you have been listening to hegerpublic radio at hegerpublicradio.org we are a community podcast
network that releases shows every weekday on day through friday today's show like all our shows
was contributed by an hbr listener like yourself if you ever consider recording a podcast
then visit our website to find out how easy it really is hegerpublic radio was founded by the
digital dot-pound and the infonomicum computer club hbr is funded by the binary revolution
at binref.com all binref projects are crowd-sponsored by linear pages from shared hosting to custom
private clouds go to lunar pages.com for all your hosting needs unless otherwise stasis today's
show is released on the creative commons at review show share a live video's own license