Before you can access files on a floppy, CDROM, zip drive, or any other device (including your hard drive), you need to tell Linux where in the directory tree you would like those files to appear. This process is called mounting the file system. Please note that you do not mount a device, you mount a file system that resides on the device. Also note that when you are done using it you should...
The ' dd ' command is one of the original Unix utilities and should be in everyone's tool box. It can strip headers, extract parts of binary files and write into the middle of floppy disks; it is used by the Linux kernel Makefiles to make boot images. It can be used to copy and convert magnetic tape formats, convert between ASCII and EBCDIC, swap bytes, and force to upper and lowercase.
For those of you'll who have no idea what Redirection means, let me explain it in a few words. Whenever you run a program you get some output at the shell prompt. In case you don't want that output to appear in the shell window, you can redirect it elsewhere. you can make the output go into a file...or maybe go directly to the printer.. or you could make it disappear :)
Like all the shells available in Linux, the Bourne Again SHell is not only an excellent command line shell, but a scripting language in itself. Shell scripting, allows you to fully utilize the shell's abilities and to automate a lot of tasks that would otherwise require a lot of commands to perform.
In this second article, Harold continues with his fast paced, excellent introduction to Bash Programming. This time he explains how to perform arithmetic operations in your bash scripts.
Python pickling support comes from the pickle module, and its cousin, the cPickle module. The latter was coded in C to provide better performance and is the recommended choice for most applications. We'll continue to talk about pickle, but our examples will actually make use of cPickle. Since most of our examples will be shown from the Python shell, let's start by showing how to import cPickle...
Over time you'll find yourself having to make changes to your class definitions. If you've already pickled instances of a class that needs changing, you'll likely want to retrieve and update those instances so that they continue to function properly with the new class definition. We already saw some of the errors that can occur when changes are made to classes or modules. Fortunately, the pickling...
Persistence is all about keeping objects around, even between executions of a program. In this article you'll get a general understanding of various persistence mechanisms for Python objects, from relational databases to Python pickles and beyond. You'll also take an in-depth look at Python's object serialization capabilities.
I certainly cannot agree with some who insist that Python is easier to read or understand than Perl. That's just ridiculous: neither of them add anything to helping understand someone else's code. Perl isn't any more "cryptic" than Python. Nor can I understand the attitude that Perl is deficient because you can do things in multiple ways. If you insist on such structure, enforce it upon...
There are several reasons why Python is gaining in popularity with Linux users. Python users don't match the sheer numbers of Perl users, but users who have tried Python tend to continue using it for these simple reasons:
Columnist Evelyn Mitchell gives an introduction to Python, a unique, open-source scripting language popular with many Linux coders. Once you have glimpsed the power and simplicity of Python, you may never go back. Evelyn compares Python with Perl, Java, and Tcl, illustrating differences along the way with explicit code segments.
Google is now letting web sites submit an xml file that lists urls and some information about how often the pages change, and how important the page is relative to other pages. Basically, it gets you to do part of the work for them - which we would hope helps everyone
This section describes Python features that you can use to organize and structure your code.
Parentheses are not needed around the condition. Use parentheses to group sub-expressions and control order of evaluation when the natural operator precedence is not what you want.
The print statement automatically appends a newline to output. To print without a newline, add a comma after the last object, or use "sys.stdout".