redirects the output of a command to a file, replacing the existing contents of the file. mapfile is a BASH shell builtin, to display your local syntax from the bash prompt type: help mapfile. Command input and output can be redirected to files, other commands, or other terminals. Option One: Redirect Output to a File Only. Here we used $'\0', which means ASCII NUL character (character code 0), to match with -print0 used with find.It's clear that the delimiter used by find and mapfile must match for the command to make sense. In recent bash versions, use mapfile or readarray to efficiently read command output into arrays $ readarray test < <(ls -ltrR) $ echo ${#test[@]} 6305 Disclaimer: horrible example, but you can prolly come up with a better command to use than ls yourself The cut command is used in Linux and Unix systems to cut parts and sections from each line of a file and write the result to standard output. To use bash redirection, you run a command, specify the > or >> operator, and then provide the path of a file you want the output redirected to. >> redirects the output of a command to a file, appending the output to the existing contents of the file. You can capture stderr to variable and pass stdout to user screen (sample from here):. 4. Capture the output of a script inner.sh and store it in an array called myarray: mapfile -t myarray < <(./inner.sh) Based on my Bash experience, I’ve written Bash 101 Hacks eBook that contains 101 practical examples on both Bash command line and shell scripting. exec 3>&1 # Save the place that stdout (1) points to. For example, let's say you write a bash script that requires input of a … Sometimes, we may not wish to see that output. Whenever we run a Bash command on our Linux Mint 20 terminal, the regular practice is to see some output on the terminal. The <(COMMAND) is called process substitution. output=$(command 2>&1 1>&3) # Run command. 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bash mapfile from command output