TidBITS#666/10-Feb-03
=====================
Apple seems to be on a weekly hardware release cycle these days,
with last week's release of the "Spring Line" of flat-panel
iMacs (along with eMac price drops) and this week's release
of new Xserves. We examine both, but devote the bulk of the
issue to Kirk McElhearn's tutorial on navigating via the
command line. In TidBITS news this week, find out how you
can get pre-publication chapters of Adam's iPhoto book and
see him this week in New York City.
Topics:
MailBITS/10-Feb-03
Apple Revs Xserve and Introduces Xserve RAID
A Mac User's Guide to the Unix Command Line, Part 2
<http://www.tidbits.com/tb-issues/TidBITS-666.html>
<ftp://ftp.tidbits.com/issues/2003/TidBITS#666_10-Feb-03.etx>
Copyright 2003 TidBITS Electronic Publishing. All rights reserved.
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MailBITS/10-Feb-03
------------------
**Bit of Numerology** -- We hit these triple identical digit
issues of TidBITS every couple of years, but this is one of the
most notable, since 666 is the so-called "number of the beast"
from the Bible's Book of Revelation (Chapter 13, verse 18). But
the number has additional meaning in the Macintosh world, where
$666.66 was the initial price of the Apple I and where the now-
relevant Unix command chmod 666 unlocks certain problematic files.
It turns out the number has many other mathematical properties,
as you can read at Mike Keith's page on the topic. I particularly
like the last one. [ACE]
<http://www.htmlbible.com/kjv30/B66C013.htm>
<http://users.aol.com/s6sj7gt/mike666.htm>
**Apple Releases New iMacs, Lowers eMac Prices** -- Continuing the
push to update its product line for AirPort Extreme and Bluetooth,
Apple last week unveiled the latest revisions to its flat-panel
iMac line. The new 17-inch iMac starts at $1,800 and boasts a 1
GHz PowerPC G4 and a 133 MHz system bus, 256 MB of DDR SDRAM
(expandable to 1 GB), and a 4x SuperDrive (CD-RW/DVD-R), along
with slots for an AirPort Extreme card (an extra $100), and an
internal Bluetooth module (an extra $50). The 15-inch iMac
receives only a speed bump to an 800 MHz PowerPC G4 and a $200
price drop to $1,300. Unfortunately, it's not capable of taking
an AirPort Extreme card (though the slower 802.11b AirPort card
remains an option) and can use only a USB-based Bluetooth adapter.
Simultaneously, Apple announced price cuts - but no new features -
for the 17-inch CRT-based eMac, which now costs $1,000 with a
Combo drive (CD-RW/DVD-ROM) or $1,300 with a SuperDrive. [ACE]
<http://www.apple.com/imac/>
<http://www.apple.com/emac/>
**Get Pre-Publication iPhoto 2 VQS Chapters** -- As the latest in
my efforts to experiment with various approaches to electronic
publishing, I will be making available for download each chapter
in my forthcoming book, iPhoto 2 for Mac OS X: Visual QuickStart
Guide. Most people who use iPhoto have probably upgraded to iPhoto
2, but I see no reason why people who want to buy the book should
wait for all the unavoidable aspects of print publishing
(especially for international readers) that delay the arrival
of a book. So here's the deal. If you pre-order my iPhoto 2
book on Amazon, from Peachpit, or any other source, and send
your receipt to <[EMAIL PROTECTED]>, I'll send you the
instructions for getting each chapter in PDF format as soon as
I finish writing and Tonya finishes editing. I'll also add you
to a mailing list that will receive announcements when I upload
a new chapter. At the end, I'll post the entire book as a single
PDF with the bookmarks and links that can make an electronic book
even more useful than a physical copy. And of course, when the
paper copy comes out, it will arrive on your doorstep as soon
as possible.
A few notes about different retail outlets: Since I'm handling
all this myself ("if you want something done right..."), it
really doesn't matter where you choose to pre-order the book
as long as you can send me a receipt via email. However, I've
noticed that Amazon is not yet discounting the $20 book their
usual 20 to 30 percent, so you'll pay a bit more there right
now. Other booksellers may offer a discount and reasonable
shipping rates. [ACE]
<http://www.amazon.com/exec/obidos/ASIN/0321197763/tidbitselectro00/>
**Adam Speaking at NY City Area User Groups This Week** -- On
Thursday, 13-Feb-03 at 6:30 PM, I'll be speaking at the monthly
MetroMac meeting at New York University, and on Friday, 14-Feb-03
at the Long Island Macintosh Users Group (LIMac) at the New York
Institute of Technology. At both meetings I'll be talking about
the most interesting products and events from Macworld Expo in
San Francisco and answering questions about wireless networking,
iPhoto 2, and anything else people want to ask. I should have
signed copies of my books to raffle off, and I'll be happy to sign
copies you already have. And yes, since Friday is Valentine's Day,
that meeting will be a family affair: Tonya and Tristan are coming
to the LIMac meeting. Directions to the meeting locations for both
are on the groups' Web sites. [ACE]
<http://www.metromac.org/>
<http://www.limac.org/>
**Digital Photography Cruise in June** -- Alaska in June is a
fabulous place for outdoor photography thanks to its gorgeous
scenery and great evening light from the longest days of the year.
If you're interested in honing your digital photography skills,
you might want to check out the upcoming Digital Photography
Workshop at Sea with lead instructor Arthur Bleich, who
contributes to TidBITS on digital photography topics. [ACE]
<http://www.dpcorner.com/cruise/>
Apple Revs Xserve and Introduces Xserve RAID
--------------------------------------------
by Adam C. Engst <[EMAIL PROTECTED]>
Leaving the iBook as the only part of Apple's product line that
hasn't recently received a significant update (hint, hint), Apple
today announced new models of their industrial strength Xserve 1U
rack-mount servers (see "Apple Introduces Xserve Rack-Mount
Server" in TidBITS-631_). Simultaneously, Apple introduced the
Xserve RAID, a 3U rack-mount 2Gb Fibre Channel box that can hold
up to 14 Apple Drive Modules for a total of 2.52 terabytes (TB) of
storage. Apple had originally promised the Xserve RAID would be
available by the end of 2002, but the company backtracked toward
the end of the year. Both the new Xserve models and the Xserve
RAID will be available in March.
<http://db.tidbits.com/getbits.acgi?tbart=06828>
Competing as they do in the big business world of data centers,
the Xserve and Xserve RAID will live and die by their specs, and
Apple has provided what look like impressive numbers.
**New Xserves** -- The new models feature either one or two 1.33
GHz PowerPC G4 processors with 256K of on-chip Level 2 cache
running at the full 1.33 GHz speed and 2 MB of Level 3 cache, all
using a 167 MHz system bus. They come with either 256 MB or 512 MB
of PC2700 DDR RAM running at 333 MHz (upgradable to 2 GB via four
DIMM slots), and one 60 GB ATA/133 drive module (with a maximum of
720 GB possible by filling the four hot-swappable drive bays with
180 GB drive modules). Also new are a pair of FireWire 800 ports
on the back panel that join the standard two USB ports and a DB-9
serial port; the front panel offers a single FireWire 400 port.
Dual independent Gigabit Ethernet is still standard, as is a
PCI-based ATI video card (an AGP 4x ATI Radeon 8500 can replace
the Ethernet card in the combo PCI/AGP slot). You can now choose
a Combo drive (CD-RW/DVD-ROM) instead of the standard CD-ROM
drive. As before, a copy of Mac OS X Server with unlimited clients
runs the Xserve. The single processor model starts at $2,800 and
the dual processor model at $3,800, both a drop of $200 from the
slower models they replace.
<http://www.apple.com/xserve/>
<http://www.apple.com/pr/library/2003/feb/10xserve.html>
A few notable things have not changed. The new models do
not support either AirPort Extreme or Bluetooth, but neither
technology makes much sense for a rack-mounted server. The Xserve
still lacks dual power supplies, which some people have longed
for, and maxes out at 2 GB of RAM, rather than the 4 GB or 8 GB
that some high-end installations need.
<http://db.tidbits.com/getbits.acgi?tlkthrd=1655+1703>
**Xserve RAID** -- Apple's new Xserve RAID connects to the Xserve
via the $500 dual channel 2 GB Apple Fibre Channel PCI Card.
Rather than use pricey Fibre Channel drives, the Xserve RAID
relies on inexpensive 7200 RPM ATA/100 drive modules that can be
hot-swapped into the 3U rack mount enclosure that converts ATA
to Fibre Channel. Each 3U enclosure can hold up to 14 Apple Drive
Modules (the same hot-swappable modules used in the Xserve itself)
for a total of 2.52 TB. For reliability, the Xserve RAID offers
optional Cache Backup Battery Modules that Apple claims provide
more than 72 hours of backup power to protect data in the RAID
controller during a power outage; dual independent RAID
controllers, redundant cooling modules; and dual, redundant,
hot-swappable power supplies.
<http://www.apple.com/xserve/raid/>
<http://www.apple.com/pr/library/2003/feb/10xserveraid.html>
The Xserve RAID may cost less than other high-end hardware RAIDs,
but it's still not exactly cheap: 2.52 TB costs $11,000 (about
$4 per GB), though you can buy 1.26 TB for $7,500 and 720 GB for
$6,000. In terms of RAID levels, the Xserve RAID supports RAID 0
(striping), RAID 1 (mirroring), RAID 3 (striping with parity),
RAID 5 (striping with distributed parity), and RAID 0+1 (striping
over mirroring). That's all in hardware; software RAID in the
Xserve adds RAID 10, 30, and 50, which is striping across multiple
RAID 1, 3, or 5 sets.
**Slow Start, but Great Expectations** -- The Xserve hasn't been
a barn-burner in terms of sales and didn't even meet Apple's
projections in the second quarter of 2002, its first quarter of
sales, Still, the Gartner Group said Apple shipped 5,700 units
in the U.S. in the third quarter of 2002, good for a 1.2 percent
market share that was three times better than the previous year's
third quarter. And in the fourth calendar quarter of 2002, Apple
said it shipped 6,000 Xserves. Those numbers don't sound like
much, but the market for high-end servers is much smaller than
for desktop computers (in a year, Apple alone ships nearly as
many Macs in the U.S. as the total U.S. server sales from all
companies).
<http://www3.gartner.com/5_about/press_releases/2002_10/pr20021028b.jsp>
Nonetheless, the Xserve has received generally glowing reviews
from publications that are seldom enthused about anything from
Apple. The prices are competitive, the software is a tremendous
value (it would cost $1,000 on its own), and there's no question
that Apple has improved the Xserve in welcome ways. Dual power
supplies may be unreasonable in a 1U case - there simply isn't
much extra room in there - but it would be good to see Apple
raising the upper limits on RAM in a future revision. But you
already know if those limitations are a problem for your needs;
for most people who need a server, a rack-mounted Xserve is an
impressive package, particularly for the price. I hope to be
ordering one soon for our next generation of TidBITS server
infrastructure.
PayBITS: Did Adam's Xserve research and reporting help make up
your mind about whether or not the Xserve is your next server?
<https://www.paypal.com/xclick/business=ace%40tidbits.com>
Read more about PayBITS: <http://www.tidbits.com/paybits/>
A Mac User's Guide to the Unix Command Line, Part 2
---------------------------------------------------
by Kirk McElhearn <[EMAIL PROTECTED]>
Lesson 2: Navigating the File System
In the first installment of this series, we looked at the basics
of using the Terminal to access Mac OS X's Unix core. What's next?
Well, when you visit a new place, the first thing you need to
learn is how to get from one location to another. So, let's look
this time at how you use the Terminal to move around your Mac's
file system. (You might want to go back and read the previous
article again to refresh your memory before continuing.)
<http://db.tidbits.com/getbits.acgi?tbart=07003>
As you are certainly already aware, your files are organized in a
hierarchy of directories (the Unix word for folders). When moving
around in the Finder, you open folders, which display other
folders and files, and you drag, copy and paste files and folders
among the windows that the Finder displays. In the Unix world,
you navigate among directories using commands, displaying lists
of files and directories, and you move, copy and paste files and
directories from the command line.
In most cases, you're probably better off using the Finder for
your everyday activities. But navigating the file system with
the Terminal can have a few advantages:
* It's fast. You can jump from one directory to another in a
split-second, as long as you know its path. There's no need
to open window after window to get where you want.
* It's informative. While you can access most of the same
information from the Finder - such as file permissions - the
Terminal displays these details more quickly. For example, you
can use the Finder's Get Info window to learn the permissions
for an entire folder of files, but you must do so individually
for each file. With the Terminal, you can display a list showing
permissions for all the files instantly.
* It's complete. You can access invisible files and directories
that aren't accessible via the Finder (without special utility
software). In most cases, you're better off leaving these files
and directories alone, but if you need to see or work with
invisible files and directories, the Terminal may be the best
way to go.
**Navigating the Mac OS X File System** -- Mac OS X, like most
other operating systems, uses a file system to organize files
and folders. The basic principle behind this system is that of
hierarchy: at the top of the hierarchy is a single point (called
the "root" of the file system, indicated by / in Unix systems),
and below that point, a tree structure spreads out from directory
to sub-directory.
In the Finder, you can easily see tree structure by looking at a
window in column view. Open a new Finder window, choose View > As
Columns, click on your startup disk, then Users, and then your
user name. You should see at least eight folders in the fourth
column. You're looking at the contents of your Home folder. Each
of its sub-folders can contain other files and folders, and so on.
The rest of this article will show you how to move around in your
Mac's file system using the Terminal. You will learn how to
display the contents of a directory, how to change directories,
and how to determine where you are.
Bear in mind that whenever you open the Terminal you are at a
specific location in the file system. Unless you've modified
how the Terminal works on your Mac (at which point you probably
don't need these articles), you will always begin in your Home
directory, the one with your user name (such as mine, called
kirk). No matter what you do in the Terminal, you are always
someplace.
**Finding Where You Are with pwd** -- When traveling, you
sometimes need to look at a map to find where you are. The same
goes for the Terminal. The pwd command (print working directory)
does just that by telling the Terminal to display the full path
to the current working directory.
[Walden:~] kirk% pwd
/Users/kirk
I left the complete prompt visible in the above example to show
you the difference between the directory information visible in
the prompt (the ~) and what pwd displays. The only difference is
that my user's Home directory is replaced by the ~ shortcut. But
look at the next example. When I'm outside my Home directory,
there's no difference between what is shown in the prompt and
what pwd returns.
[Walden:/Library/Preferences] kirk% pwd
/Library/Preferences
**Listing Directory Contents with ls** -- The ls command (list
directory contents) is one of the most useful and commonly used
commands for navigating the file system. You're used to seeing the
contents of folders when opening new windows in the Finder; when
you move to a new directory in the Terminal, you see nothing. The
Terminal only displays the contents of a directory after you tell
it to with the ls command.
When you are in your Home directory, and run the ls command, you
should see something like this:
% ls
Desktop Library Music Public
Documents Movies Pictures Sites
The ls command returns a simple list of the current working
directory's contents, but nothing in this list tells you anything
about what these items are. Luckily, the ls command offers a
plethora of options on how to display the contents of a directory,
and what type of information is shown.
**Viewing the Contents of a Different Directory** -- The ls
command displays the contents of the current working directory
(the one the Terminal is in) if you do not add the name of a
directory to the command as an argument. You can list the contents
of any directory on your computer, as long as you know its path.
To do this, you must specify the full path of the directory. For
example, if you want to list the contents of the /Library/Fonts
directory, enter the following:
% ls /Library/Fonts
Arial Cochin.dfont HelveticaNeue.dfont
Arial Black Comic Sans MS Hoefler Text
Arial Narrow Courier New Optima.dfont
[etc.]
You must use the complete path of the directory /Library/Fonts/,
because you are specifying an absolute file path. However, you can
also use ls to display the contents of directories using relative
file paths. When in my Home directory, I can display the contents
of the Pictures directory by simply entering the following:
[Walden:~] kirk% ls Pictures/
iPhoto Library white background.jpg
As you can see from the prompt, I am still in my Home directory
(~). If you don't specify an entire file path beginning with /, ls
assumes you want to start from the current working directory.
**Viewing the Entire Contents of a Directory** -- The basic ls
command displays the contents of a directory in a simple manner.
But what this command doesn't tell you is that there are other
items in the directory. In fact, every Mac OS X directory contains
invisible items, either files or folders. To view the entire
contents of a directory, use the ls command with the -a option.
(Note that options go _before_ the directory path, if you're
listing the contents of a specific directory as discussed
just previously.)
% ls -a
. .Trash Desktop
.. .addressbook Documents
.CFUserTextEncoding .addressbook.lu Library
.DS_Store .lpoptions Movies
[etc.]
Your Home directory may contain different files, but many of
them are the same. As you can see, there are a series of files
beginning with . (dot). This dot indicates that a file is
invisible, and the ls -a command displays all files, including
invisibles. While you won't need to access most of these files
(and messing with some of them could be harmful to your system),
you can see them and know they are there. (Later in this article,
when examining the cd command, we'll see what . and .. do.)
**Viewing Long Information** -- Another option to the ls command, -l
(that's a lowercase L), returns much more complete information
on the contents of a directory, going much further than what you
can find out from the Finder's Get Info command. If I run ls -l in
my Home directory, the Terminal returns the following information:
% ls -l
total 0
drwxr-xr-x 3 kirk staff 102 Nov 9 11:22 Applications
drwxr-xr-x 8 kirk staff 272 Nov 11 14:46 Desktop
drwxr-xr-x 24 kirk staff 816 Nov 11 13:07 Documents
drwxr-xr-x 44 kirk staff 1496 Nov 10 22:49 Library
[etc.]
When you use ls with the -l option, the following information is
displayed:
* The first line shows the number of 512-byte blocks used by files
in the directory. In this example, there are no files - only
directories - so it reads total 0.
* The first part of each line shows the file or directory's
permissions.
* The next part is a number, showing the number of file system
links the file or directory uses.
* Then comes the user name. In the above example, I am in my Home
directory, so all the files belong to me.
* Next is the group the user belongs to. In this case, I belong
to staff.
* The next number is the size of files in bytes, or the number of
directory entries. This number is useful for files; the directory
number is less useful.
* The date and time shown correspond to the last time the file or
directory was modified. If the file has not been modified in the
last year, the date and year are shown.
* Finally, the name of the file or directory is shown.
If you use ls -l in other locations, you may see additional
information:
* Items belonging to other users, such as root.
* Additional groups, such as wheel, unknown, and admin, in
addition to staff.
* Some items contain -> in their names. These are symbolic links,
similar to Mac OS aliases. For example, var -> private/var is a
symbolic link pointing from var to private/var.
While the ls -l command shows the size of files, there are some
cases where this figure is incorrect. Adding the -s option adds a
column, at the left of the list, showing the number of 512-byte
blocks each file takes up on disk. Look at the following example:
% ls -ls
328 -rw-r--r-- 1 kirk staff 30819 Nov 14 18:06 Perceval.jpg
64 -rw-r--r-- 1 kirk staff 30819 Nov 14 18:07 PercevalCopy.jpg
These two files seem to have the same size (30819 bytes) but the
first file takes up much more space on disk. This is because the
first file, a picture, has an additional resource that the
Terminal does not see. This thumbnail takes up much more space
than the actual file, and the Finder clearly shows the difference
in size. But the Terminal does not unless you use the -s option.
**Changing Directories with cd** -- When navigating your Mac's
file system in the Finder, you have two choices: you can either
have the Finder open a new window when you open a folder, or it
can open the new folder in the same window. When working in this
second way, you always have just one window open, and you can go
backward and forward in your file system hierarchy, but always
within the same window.
Moving around in the Terminal works in this second way: no matter
where you move to, you are always "in" one directory. As we saw
above, the Terminal prompt tells you which directory you are in,
and the pwd command tells you where you are in the file system
hierarchy. So, remember that, when navigating the file system in
the Terminal, you are always in one location.
The cd command (change directory) moves you from one directory to
another. In Unix lingo, it changes the working directory; this is
the directory in which you are located, and the one in which you
can act on enclosed files or directories without specifying a file
path. Let's start by looking at the following:
[Walden:~] kirk% ls
Desktop Library Music Public
Documents Movies Pictures Sites
The above shows the contents of my Home directory after executing
the ls command. To move to the Library directory, type the
following and press Return:
% cd Library
[Walden:~/Library] kirk%
The prompt changes to reflect the current working directory.
(If you need to move into a folder whose name contains more than
one word, enclose the folder name in quotes.) Then, to see what
it contains, type ls and press Return.
% ls
Addresses FontFavorites.plist Preferences
Application Support Fonts Printers
Assistants Fonts (Disabled) Recent Servers
Audio Frameworks Screen Savers
[etc.]
You can move into one of these directories with cd:
% cd Addresses
[Walden:~/Library/Addresses] kirk%
And, look at its contents, using ls:
% ls
Address Book.addressbook Addresses.addressBook
At this time, you may have forgotten where you are in your file
system. Use the pwd command to learn your location:
% pwd
/Users/kirk/Library/Addresses
You can now use the cd command to move back up in the hierarchy by
running cd with the complete file path of the folder you want to
move to. Say you want to go back to the Users/ directory; use the
following:
% cd /Users
[Walden:/Users] kirk%
The prompt shows that you are in the Users directory. If you want
to go back to the Library directory, where you were before, you
could type the following:
% cd /Users/kirk/Library/
[Walden:~/Library] kirk%
If you attempt to move into a directory that does not exist, or
if you misspell the name of a directory, you see this message:
% cd Proust
Proust: No such file or directory.
**Using the Finder to Save Time in the Terminal** -- While you may
think that the Finder and the Terminal are mutually exclusive, the
two can work together to save you time. Sometimes, you may need to
type a lot to get into a deeply nested directory, but it's a cinch
to navigate there in the Finder. If you want to move into a
directory using cd, type cd [space] in the Terminal. Then switch
to the Finder, look for the folder you want to move to, and drag
that folder into the Terminal window. The Terminal adds the path
of the item you drag to the command you just typed.
[Walden:~] kirk% cd /Users/kirk/Library/Preferences
Press Return, and that directory becomes your current working
directory.
You can do the same thing to act on a file. Just type the
beginning of the command you want to use (don't forget to type
a space before dragging the file), then locate the file in the
Finder, and drag it to the Terminal window.
**Going Home in a Jiffy** -- It may seem as though using the cd
command requires a lot of typing, and in its basic usage, that
can be true. However, cd also offers many shortcuts to let you
navigate quickly and easily through the file system. The most
useful shortcut is to type just cd, then press Return, which we
do while our current working directory is the Addresses directory,
as you can see in the prompt below.
[Walden:~/Library/Addresses] kirk% cd
[Walden:~] kirk%
As you can see from the second prompt, cd by itself takes you
to your Home directory. (Remember, the tilde character (~) is a
shortcut for the current user's Home directory.) The reason for
this shortcut is that Unix assumes most users will only be working
in their Home directory or one of its sub-directories. For this
reason, the tilde (~) shortcut for your Home directory also lets
you move easily to sub-directories within your Home directory. If
you want to move to your Documents directory, you can type the
following no matter where you are:
% cd ~/Documents
[Walden:~/Documents] kirk%
Using the ~ shortcut helps save you from typing the full file path
of the Documents directory.
**Upstairs Downstairs** -- Every directory in your file system
contains at least two entries. When you create a new, empty
directory, these two "files" are automatically added to them.
They are . (dot) and .. (dot dot). Look at the following:
% mkdir New_Directory
% cd New_Directory
% ls -a
. ..
In the first line above, I created a new directory, and, in the
second line, I moved into that directory. I then ran the ls -a
command, which displays the contents of that directory; the -a
option shows invisible files. You can see that the only files in
this new directory are . (dot) and .. (dot dot).
These two files are useful. The first one, . (dot), represents
the current working directory, and can save you time in certain
commands involving files within that directory. The second one, ..
(dot dot), is a shortcut to the parent directory, or the next
directory up in the file system. No matter where you are in the
file system, you can always type the following:
[Walden:~/Documents/New_Directory] kirk% cd ..
[Walden:~/Documents] kirk%
As you can see from the prompts in this example, typing cd ..
takes you up to the parent directory of New_Directory, or
Documents. Any time you move into a sub-directory, using the cd
command, you can use cd .. to back up. But you can also move up
the file system from the current directory until you reach the
top. Look at the following:
[Walden:~/Documents] kirk% cd ..
[Walden:~] kirk% cd ..
[Walden:/Users] kirk% cd ..
[Walden:/] kirk%
As you can see in the prompts, I was in my Documents folder, then
moved up three times to reach the root level of the file system,
or /.
You can now combine the cd .. command with cd - to move up and
down in the file system, but, remember, the cd - command only
moves back one step. There is no simple equivalent (in the cd
command) to move down the file system to where you started.
[Walden:/Users] kirk% cd ..
[Walden:/] kirk% cd -
[Walden:/Users] kirk%
In the first line, I moved up from /Users to /; in the second
line, I moved back to the previous working directory, /Users.
**Opening a Directory in the Finder** -- Sure, the Terminal lets
you move around quickly and easily, yet all but the most die-hard
Unix fans will eventually yearn to see icons again. Wherever you
are in the Terminal, no matter what directory you are in, you can
run the following command at any time to open the current working
directory in a new window in the Finder:
% open .
You will recall that . (dot) represents the current working
directory. The open command lets you open many kinds of items just
as if you double-click them. The open command even lets you open
directories that are normally hidden from view by the Finder, thus
giving you the best of both worlds.
**Home Again** -- This article showed you how to move around
your Mac's file system, and how to see what its folders (or
directories) contain. You learned about how the Mac OS X file
system works, and saw some of the differences between what you
see in the Finder and what Terminal shows you. You discovered
some of the basic commands for navigating your computer, which
are the command-line equivalents of double-clicking folders and
reading their contents:
* pwd: tells you where you are.
* cd: takes you into another directory.
* ls: shows you what your directories contain
* open: opens a directory in a new window in the Finder.
* You also learned how to use the ~ (tilde) character as a
shortcut for your Home directory.
In the next installment, you'll learn how to move and copy
files, how to create directories, and how to delete files and
directories, rounding out the basics of command-line navigation.
[Kirk McElhearn is a freelance writer and translator living in a
village in the French Alps. This article is an excerpt from his
forthcoming book, Unix for Mac OS X: Learning the Command Line, to
be published by Addison-Wesley in September 2003.]
<http://www.mcelhearn.com/unix.html>
PayBITS: Did this article help you dip your toes into Terminal?
Consider supporting Kirk with a few bucks via PayPal!
<https://www.paypal.com/xclick/business=kirk%40mcelhearn.com>
Read more about PayBITS: <http://www.tidbits.com/paybits/>
$$
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