Is there any way to append output(debugging information) to a existings file? As we all know in bash the command ‘>’ will write ouputs to a file.However this command will also erase the existing data it the file.
Of course bash provides a command that appends outputs to a file.It resembles ‘>’.It’s ‘>>’
The following is a piece of example code.

Let’s look at >

1
2
3
4
5
6
7
8

[androidyue@androidyue tmp]$ touch a.txt
[androidyue@androidyue tmp]$ cat a.txt
[androidyue@androidyue tmp]$ echo "ABC" > a.txt
[androidyue@androidyue tmp]$ cat a.txt
ABC
[androidyue@androidyue tmp]$ echo "DEF" > a.txt
[androidyue@androidyue tmp]$ cat a.txt
DEF

Well,Let’s look at the exiciting command >>

1
2
3
4

[androidyue@androidyue tmp]$ echo "GHI" >> a.txt
[androidyue@androidyue tmp]$ cat a.txt
DEF
GHI