Study notes, transferred from: http://blog.csdn.net/yuyongpeng/article/details/1818713
Watch archive content : cat, tac, more, less, head, tail, nl,
What we mentioned just now is only to display the appearance of the file, or to move and copy a file or directory, so if we want to inspect the content of a file, what should we do? ! There are quite a few interesting commands to share here: the most commonly used commands for displaying file contents are cat and more and less ! Also, what if we want to view a very large file (hundreds of megabytes ), but we only need a few lines from the backend? Ha ha! Use tail , in addition, the tac command can also be achieved! Well, let's talk about the purpose of each command!
cat starts to display the file content from the first line tac starts to display from the last line, it can be seen that tac is written backwards of cat ! more shows the contents of the file page by page. Less is similar to more , but better than more , he can turn pages forward! When head only looks at the first few lines, tail only looks at the tail, when nl is displayed, output the line number along the way! od reads the archive contents in binary!