Menu
Unix provides the capability to change where standard input comes from, or where output goes using a concept called Input/Output (I/O) redirection. I/O redirection is accomplished using a redirection operator which allows the user to specify the input or output data be redirected to (or from) a file.
In Linux, for redirecting output to a file, utilize the ”>” and ”>>” redirection operators or the top command. Redirection allows you to save or redirect the output of a command in another file on your system. You can use it to save the outputs and use them later for different purposes.
Sending a Message to Standard Output (echo Command) You can display messages on the screen with the echo command. For example, to write a message to standard output, at the prompt, enter: echo Please insert diskette . . .
If I redirect output of a command to same file it reads from, its contents is erased.
sed 's/abd/def/g' a.txt > a.txt
Can anyone explain why?
If you love us? You can donate to us via Paypal or buy me a coffee so we can maintain and grow! Thank you!
Donate Us With