Linux Data redirection

Number

0 standard input (stdin)

1 standard output (stdout)

2 standard error (STDERR)

Data redirection:

When executing a command, some commands execute when the result of successful execution or the process at execution and the execution of the command fail to execute the error prompt output to the terminal

Standard output, standard error output message to Terminal (Terminal) by default

Data redirection is the data that is exported by default to the terminal and uploaded to other files or devices

Use the command > file stdout to redirect to a file

Redirect the date output to the file file if the file does not exist

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Overwrite the file if it exists

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Use the command > > file to append to the current file without overwriting the original file

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Note Redirection stdout can prevent the process output from appearing on the terminal but cannot prevent STDERR error message output on the terminal

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Use the command 2> file stderr to redirect files

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The command 2>> file indicates that the stderr is appended to the file

REDIRECT stdout stderr to/dev/null and discard it (just not shown)

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REDIRECT StdOut stderr to the same file at the same time

1. Command &> file

[[email protected] ~]$ find/etc-name passwd &> file

2. Command > file 2>&1

[Email protected] ~]$ find/etc-name passwd > File 2>&1

Be careful not to think the same. Redirecting to the same file at the same time may cause confusion in the data cross-write order

[Email protected] ~]$ find/etc-name passwd > file 2> file

Append stdout stderr to the same file at the same time

Command > > file 2>&1

[Email protected] ~]$ find/etc-name passwd >> file 2>&1

This article is from the Linux Learning Notes blog, so be sure to keep this source http://10516823.blog.51cto.com/10506823/1715205

Linux Data redirection