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Trawling the Ports CollectionGreg Lehey <grog@lemis.com>One of the most important parts of the BSD distributions is the Ports Collection, called the Packages Collection in NetBSD. It neatly solves the problem of how to get third party software running on your machine, and there's something in there for everybody. The idea came from FreeBSD, which still has the largest collection of ports--nearly 7,000 of them, in fact, including just about anything you can think of. A large number of programs that are part of Linux base distributions are in the BSD Ports Collections. Of course, you can have problems with the Ports Collection:
Let's consider finding bash. If you're running FreeBSD, you could start with link to the index page on the FreeBSD home page, where you'll find a list of the ports categories and links to more details. But what category is bash in? There are 64 categories, and you may not know where to look for bash. By the time you get to Shells, somewhere near the bottom, you've compared so many others that may no longer be sure. And that's just for a program you know and you're looking for. How can you find things you don't know? And once you've found it, how do you use it? This is the first of a series of articles which addresses these issues. In particular, every month I'll dig out an interesting port or two, but first, this month I'll give a brief introduction to the Ports Collection and the environment in which I do my work. Hopefully you'll find it interesting; one way or the other, I'd be interested in feedback. Installing portsI'm assuming here that you know the basics of the Ports collection. If not, read James Howard's article in the June 2000 edition of Daemon News. That article mentions the standard way of installing a port, using make. In fact, you have three alternatives:
What's in a port?But what is zsh? Why should you want to install it? Those are the questions that I'm going to be addressing in these articles. If you look carefully at the example above, it looks as if it should be a shell. But what kind of shell? Well, there's the documentation, of course, but it would take a lot of time to read the documentation for that many ports. The Ports Collection acknowledges this problem and includes summary documentation. Again, the location depends on the version of BSD you're running:
Getting startedSo, what shall we start with? I have a few favourites which I install on every system I use for any length of time. We'll look at the shell environment this month. A shell: bashI've already mentioned bash, the Bourne Again Shell from the Free Software Foundation. It's one of a plethora of shells available, and it's the one I use. Why do I use this one? I have a number of reasons:
AlternativesThere are a number of good alternatives to bash, of course:
Installing bashWe've seen how to install ports. Simply do: # cd /usr/ports/shells/bash2 (FreeBSD, OpenBSD) # cd /usr/pkgsrc/shells/bash2 (NetBSD) # make installThat's straightforward enough. Of course, after installation you're still stuck with the same old shell you had before. You need to run chsh. This will give you an editor with details of your account, which looks something like this: #Changing user database information for grog. Shell: /bin/sh Full Name: Greg 'groggy' Lehey Office Location: Echunga SA Office Phone: +61-8-8388-8286 Home Phone: +61-8-8388-8250 Other information:Just change the /bin/sh on the second line to /usr/local/bin/bash, save and exit, and you're in business. Well, sort of. Next time you log in, you should have a bash shell. But how do you use it? Where's the documentation? The documentationbash comes with a lot of documentation, including a print manual and two man pages (bash(1) and bashbug(1)). The same content is also available as info pages. info is the GNU documentation system; we might look at it in a later article. At the moment you can live without it. bash(1) currently runs to 5144 lines, nearly 100 pages. It's probably not the sort of thing you'd want to read on line, but it's handy for searching. By contrast, bashbug(1) is very short and just tells you how to report a bug. The real documentation is in the 138 page reference manual. But where does it go? It's in /usr/local/share/doc/bash. It's available in PostScript and HTML formats: $ ls -l share/doc/bash/ total 2 -r--r--r-- 1 root bin 86238 Mar 27 14:28 article.ps -r--r--r-- 1 root bin 48004 Mar 27 14:28 article.txt -r--r--r-- 1 root bin 243837 Mar 27 14:28 bash.html -r--r--r-- 1 root bin 408887 Mar 27 14:28 bash.ps -r--r--r-- 1 root bin 8043 Mar 27 14:28 bashbug.ps -r--r--r-- 1 root bin 385523 Mar 27 14:28 bashref.html -r--r--r-- 1 root bin 654109 Mar 27 14:28 bashref.ps -r--r--r-- 1 root bin 125347 Mar 27 14:28 builtins.psYou still need to print it out, of course. That's straightforward enough if you have a PostScript printer, but otherwise you'll need ghostscript, which we'll look at some other time. Some interesting customizationsShells are infinitely customizable, and since they're one of the two main tools you use to interface with the computer (the other is the editor), it's worth making things comfortable. Everybody has his own views on this, of course. Here are some of mine. I put this in my .bashrc file:
case `tty` in
/dev/ttyp*)
TERM=xterm-color ;;
/dev/pts/*)
TERM=xterm-color ;;
/dev/ttyq*)
TERM=xterm-color ;;
/dev/ttyv*)
TERM=cons25 ;;
/dev/ttyE*)
TERM=cons25 ;;
/dev/ttyC*)
TERM=vt220 ;;
*)
TERM="" ;;
esac
export TERM
These definitions set the TERM environment variable depending on the
device name.
if [ "$TERM" = "xterm" -o "$TERM" = "xterm-color" ] ; then PS1="\[^[[34m\]=== \u@\h (`tty`) \[^[[31m\]\w\[^[[34m\] \# ->\[^[[30m\]\[^[[47m\] " else PS1="=== \u@\h (`tty`) \w \# -> " fi PS2="\u@\h \w \! ++ "The sequence ^[ is in fact an escape character. These definitions first check what kind of terminal I'm running on. If it's an xterm, it sets a prompt in colour, which makes it easy to distinguish on a large screen: === root@kimchi (/dev/ttyp1) /etc 20 ->If it's not an xterm, the prompt is monochrome, but otherwise the same. This information includes:
Next, a function definition:
Make ()
{
if [ "${MAKE}" = "" ]; then
MAKE=make
fi
xtset `uname -n|sed 's:\..*$::'`:`pwd`: Make "$* "`date`
(echo '=====' `date`: Make $*; /usr/bin/time -l ${MAKE} 2>&1 $*) | tee -a Make.log
cd .
}
This defines a function called Make. As the name suggests, it's like
make. It runs make and copies the output to a file called
Make.log. If something goes wrong in a make, you can then go back and
look at Make.log to see what happened. It also uses xtset to set
the title of the xterm to information about the build. For example, when
building a FreeBSD kernel, it is set to:
zaphod:/usr/src/sys/i386/compile/ZAPHOD: Make all -j2 -k Wed Mar 27 18:52:47 CST 2002Finally, it times the build, so I can have more of an overview over what's going on. What, you don't find xtset on your system? No, that's not surprising. It's in the Ports Collection. Well, in the FreeBSD Ports Collection, anyway. xtsetBy comparison, xtset is tiny. It takes an argument which sets the title of an xterm. If you're not running on an xterm, it does nothing. There's really not much else to say about it, though of course it comes with a man page (xtsert(1)). Here's another shell function which takes advantage of it:
cd ()
{
command cd $*
if [ $? = 0 ]; then
xtset -t "%u (%T) %h:%D"
xtset -i "%u@%h:%D"
true
else
false
fi
}
This command redefines the cd builtin command. First it executes the
builtin, then it uses xtset to set the titles separately for the xterm
window and the icon. The format is similar to that of the prompt. When in my
home directory, the title is
grog (ttyp1) wantadilla:~This can get rather long for an icon, so the icon format is different: grog@wantadilla:~xtset is in /usr/ports/x11/xtset on FreeBSD. If you're using NetBSD or OpenBSD, don't despair: pick up the tarball from ftp://ftp.lemis.com/pub/xtset-1.0.tar.gz and install it manually. It's not quite as easy as installing it from the Ports Collection, but it's not that difficult either. But why should you bother? There are good reasons: as I write this article, I have 77 windows open, spread across 5 screens. More than half of those are xterms, spread over about 10 machines. Just finding which is which becomes a challenge; xtset helps. More information about the Ports and Packages collectionsThese articles aren't intended to be a complete guide to the Ports Collections. If you don't have any background in installing ports, you may find it heavy going. You can get more information from these links: |