Mac OS X Leopard - ARCAism

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CHAPTER 18 INTRODUCING DARWIN AND THE SHELL
Leopard:~ scott$ find ~/Documents/Shakes*
/Users/scott/Documents/Shakespeare
/Users/scott/Documents/Shakespeare/macbeth
/Users/scott/Documents/Shakespeare/macbeth/soliloquy4
/Users/scott/Documents/Shakespeare/nothing
/Users/scott/Documents/Shakespeare/tomorrow
Listing directories is nothing new, but find becomes very useful with its ability to search for
matches of specific file properties, the most popular being the name of the file. To use find this
way, we give find the directory we wish to traverse, and then enter the -name option, followed by
our search string. For example, if we were looking for our soliloquy in our Documents folder, we
could use the following:
Leopard:~ scott$ find ~/Documents -name "sol*"
/Users/scott/Documents/Shakespeare/macbeth/soliloquy4
Other properties that you can use as search parameters for find include the file’s owner and
its group.
NOTE When using find, it’s best to have a good general idea of the location of the file you
are looking for. While it’s perfectly acceptable to do something like find / -name "sol*", find
is not a fast command, so in addition to getting a number of false hits and warnings (mostly
Permission Denied warnings from subdirectories that find isn’t allowed to look in), it would
take a relatively long time to perform such a search.
Unlike find, whereis is tailored specifically for finding executable files. It does this by specifically
searching the common places where programs live (primarily the various bin and sbin
directories for a specific program name you enter). For example, if you wanted to see where the
whereis command is located, you could do this:
Leopard:~ scott$ whereis whereis
/usr/bin/whereis
While this may seem trivial on a certain level, there are a couple of good reasons to use this.
First, if you occasionally compile or install your own Darwin software (which we’ll talk about in
the next chapter), at some point you may end up with two copies of the same program, and
whereis will help you find them so you can deal with it. Second, scripts written in languages like
Perl, Python, or Ruby often want to know where the language executable is, and whereis is a
quick way to determine that.
lipo
NOTE Two other commands worth mentioning here are locate and mdfind. locate searches
its database for matches to your query, which makes it quite a bit faster than find—however,
it’s possible that what you are looking for isn’t in the database. mdfind is a command unique to
Mac OS X that actually searches on Spotlight’s metadata. This makes it very fast and powerful—
however, there is one minor setback in that Spotlight doesn’t always index items until they are
opened in the Finder. So, for example, our soliloquy4 text file may not show up in an mdfind
search (or Spotlight search), at least until it is accessed by a non-Darwin application. As such,
mdfind wouldn’t be a first choice for looking for something in the Darwin file system on the
whole (however, it’s an excellent choice if what you are looking for is visible in the Finder).
lipo is a command that has special meaning to Mac OS X universal binaries. When Apple
switched hardware platforms from the PowerPC architecture to the Intel architecture, they introduced
the universal binary, which allows the application to run natively on both platforms.
Whether you are running an older PowerPC Mac or a newer Intel Mac, you probably don’t need