Table of Contents
unix Keyword 1
File Operations
Definition
The Processes of manipulating data and directories. Some examples of this are; reading, writing, creating, seeking and appending files or directories.
Creating a file or directory is essentially the same as writing in the sense of once the program is written, it has to use a compiler to convert it to machine language. Once it is converted, then it can be put in any directory specified and then called upon at a later time to execute
Reading a file is the process of the computer taking the output information that only the computer understands and converting into information that is readable to us. This process is done by interpreters and translators within the computer system.
Writing a file is the process of converting from a natural human language to a language the computer can understand. After writing a code in the system, a compiler such as VI is used in order to convert the information into an executable format that the computer can understand
Seeking is the process of repositioning the file read/write offset. This is done by using what is called a pointer, a pointer refers directly or (points to)information that is stored at another location in memory. So in other words, if the you cannot see the information until the information is “pointed to” or called from memory.
Appending a file is the process of rewriting a file that has already been written. This is done by pointing to the end of the text that was written and adding more the text desired
References
List any sites, books, or sources utilized when researching information on this topic. (Remove any filler text).
- Harley Hahn's Guide to Unix and Linux
unix Keyword 1 Phase 2
Quotes
Definition
When using the double quotes, it means to quote exactly what is inside and disable any special characters that are within the quotes.
When using singlw quotes, the output, will always get you exactly what's inside the quotation marks, any special characters are disabled from their special meaning and just printed literally.
The use for the back quote is command substitution. Meaning that you are trying to replace something within the command with whatever is in the back quote.
References
www.codecoffee.com/tipsforlinux/articles/26 www.java-samples.com/showtutorial.php?tutorialid=1333 scott.sherrillmix.com/…/using-quotation-marks-effectively-in-unix/
Demonstration
Demonstration of the indicated keyword.
#include <stdio.h>
int main()
{
printf("hello, world!\n");
return(0)
}