Capturing command output lines at once, in an array: To capture the lines output by an arbitrary command in an array , use the following: bash < 4 (e.g., on OSX as of OS X 10.9.2): use read -a 4. Sometimes, we may not wish to see that output. If you’ve been thinking about mastering Bash, do yourself a favor and read this book, which will help you take control of your Bash command line and shell scripting. output=$(command 2>&1 1>&3) # Run command. That is why we prefer suppressing the actual output of the Bash commands or scripts in a way that only their errors (if any) are displayed on the terminal. In recent bash versions, use mapfile or readarray to efficiently read command output into arrays $ readarray test < <(ls -ltrR) $ echo ${#test[@]} 6305 Disclaimer: horrible example, but you can prolly come up with a better command to use than ls yourself Examples. >> redirects the output of a command to a file, appending the output to the existing contents of the file. The <(COMMAND) is called process substitution. The second argument, "${MAPFILE[@]}", is expanded by bash. Command input and output can be redirected to files, other commands, or other terminals. You can capture stderr to variable and pass stdout to user screen (sample from here):. mapfile is a BASH shell builtin, to display your local syntax from the bash prompt type: help mapfile. We used the < <(COMMAND) trick to redirect the COMMAND output to the standard input. Then, we redirect the file to standard input using the < FILE. It makes the output of the COMMAND appear like a file. -type d) ) The IFS=$'\n' tells bash to only split the output on newline characcters o get each element of the array. When you run the whole command, mapfile silently reads our three lines of text, and places each line into individual elements of the default array variable, MAPFILE. Option One: Redirect Output to a File Only. Generally, redirecting output is much more common that redirecting input. Here we used $'\0', which means ASCII NUL character (character code 0), to match with -print0 used with find.It's clear that the delimiter used by find and mapfile must match for the command to make sense. mapfile (also known as readarray) reads lines from the standard input an array variable.-d is to specify a line delimiter instead of the default newline. Capture the output of a script inner.sh and store it in an array called myarray: mapfile -t myarray < <(./inner.sh) For example, let's say you write a bash script that requires input of a … Whenever we run a Bash command on our Linux Mint 20 terminal, the regular practice is to see some output on the terminal. Naturally, when you have a more complicated bash script, you'll see more telling output from the command. The cut command is used in Linux and Unix systems to cut parts and sections from each line of a file and write the result to standard output. While putting it in quotes as @muru suggested will indeed do what you asked for, you might also want to consider using an array for this. We can verify this using printf to print the elements of the array.. printf "%s" "${MAPFILE[@]}" The first argument, "%s" is the printf format string. exec 3>&1 # Save the place that stdout (1) points to. A read loop is far more portable but is significantly slower tham mapfile. For example: IFS=$'\n' dirs=( $(find . Explanation. Thus, the readarray command can read the output of the COMMAND and save it to our my_array. > redirects the output of a command to a file, replacing the existing contents of the file. 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. It can be used to cut parts of a line by byte position, character and field (delimiter). There is no way to capture both without temp file. 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