File Redirection
There are 3 types of standard out and
output in Linux
|
Type |
Definition
|
| Stdin |
Standard Input, which
default is keyboard |
| Stdout |
Standard Ouput, which
default is screen |
| Stderr |
Standard Error
Output, which default is screen |
You have an option to redirect the above standard input
and output to by appling the following symbols
| Symbols |
Definition |
|
> |
This will redirect the
stdout output to another input location such as file.
Note: When you apply > to a file, the previous
content of the file will be overwrritten!
|
echo "abc" > test.txt
cat test.txt
abc
echo "123" > test.txt
cat test.txt
123
|
|
|
>> |
This will redirect the
stdout output and appended to another input location such as file.
echo "456" >> test.txt
cat test.txt
123
456
|
|
|
2> |
This will redirect both
standard output and error output to another input location such as
file. The following example shows the error
message was directed to error.txt.
find /etc/sysconfig/network
Micheal &> error.txt
ls -l
total 44
drwxr-xr-x 2 root root 4096 Nov 29 17:19 Dir_empty
-rw-r--r-- 1 root root 64 Nov 30 01:22 error.txt
-rw-r----- 1 root root 0 Nov 30 00:10 jane
drwxr-xr-x 2 root root 4096 Nov 28 16:00 myDir
drwxr-xr-x 2 root root 4096 Nov 28 15:43 newmyDir
-rw-r--r-- 1 root root 8 Nov 30 00:59 test.txt
[root@srv1 demo]# cat error.txt
/etc/sysconfig/network
find: Micheal: No such file or directory
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