Differences

This shows you the differences between two versions of the page.

--- linux_wiki:use_input-output_redirection [2016/02/28 22:48]
billdozor created
+++ linux_wiki:use_input-output_redirection [2019/05/25 23:50]
@@ Line 1: / Line 1: @@
-====== Use Input-output Redirection ======
-**General Information**
-Using input/output redirection (>, >>, |, 2>, etc.).
-----
-**> Redirect standard output to a file, overwrite contents**
-<code bash>
-cat /etc/system-release > info.txt
-</code>
-**>> Redirect standard output to file, append to file**
-<code bash>
-tail /etc/passwd >> info.txt
-</code>
-**| Piping output to other commands**
-<code bash>
-cat /etc/passwd | wc -l
-</code>
-Count the number of lines in /etc/passwd
-**2> Redirect standard error**
-<code bash>
-ssh admin@webserver01.com "uptime" 2>/dev/null
-</code>
-SSH to webserver01.com, issue the uptime command, send standard errors to /dev/null (to nowhere)
-**Redirect both standard error and standard output**
-<code bash>
-ssh admin@webserver01.com "uptime" &> results.log
-</code>
-**Redirect standard error to standard out**
-<code bash>
-cat /etc/system-release /etc/Red 2>&1 | grep Red
-</code>
-Standard output can be passed through a pipe to the next command. By redirecting standard error to standard output, any error messages are successfully sent through as well.
-----