One of the fundamental challenges with modern computers is finding files and information. Whether you’re highly organized and use wonderfully mnemonic names for every file or directory you create, or whether you have lots of letter1, letter2, and work directories scattered around your filesystem, there will undoubtedly come a time when you need to find something on your computer based on its contents, filename, or some other attribute.
It turns out that there are four different ways in Unix to search for—and hopefully find—what you seek. To look inside files, you need to use the grep command, introduced briefly in the previous chapter. To find files by filename, the fastest solution is the locate command. A more sophisticated filename and attribute search can be done with the Unix power user’s find command. And finally, OS X includes a search system called Spotlight that has a powerful command-line component that’s worth exploring.
The grep program searches the contents of files for lines that match the specified pattern. The syntax is:
grep pattern [file(s)]
The simplest use of grep is to search for files
that contain a particular word by feeding grep a
pattern and a list of files in which to search. For example, let’s search
all the files in the working directory (using the wildcard
*) for the word “Unix”:
$ grep "Unix" * ch01:Unix is a flexible and powerful operating system ch01:When the Unix designers started work, ...