REDIRECTION
Generalizations
Congratulations! You learned how to use the command line to redirect standard input and standard output. What can we generalize so far?

Redirection reroutes standard input, standard output, and standard error.
The common redirection commands are:

redirects standard output of a command to a file, overwriting previous content.

redirects standard output of a command to a file, appending new content to old content.
< redirects standard input to a command.
| redirects standard output of a command to another command.
A number of other commands are powerful when combined with redirection commands:

sort: sorts lines of text alphabetically.
uniq: filters duplicate, adjacent lines of text.
grep: searches for a text pattern and outputs it.
sed : searches for a text pattern, modifies it, and outputs it.

posted on 2017-11-24 22:16  混沌奇迹  阅读(330)  评论(0编辑  收藏  举报