redirect output

use >

> should be preceded with a number, such as 2>  , but default is 1 if no number

ex:

ls > output

equals   

ls  1> output

ex:

Sending Both Output and Error Messages to Different Files

test 1> messages.out  2> message.err 

or 

test > messages.out  2> message.err 

2 means STDERR

add & after >:

means the output is redirected to a file descriptor

ex:

ls >& 2

write STDOUT & STDERR to the same place:

ex:

ls >& outfile 

or 

ls > outfile 2>&1