mapfile

Read file into array

$ mapfile [array] < [file.txt]

$ mapfile -n [10] [array] < [file.txt]

$ mapfile -s [2] [array] < [file.txt]

$ mapfile -t [array] < [file.txt]

$ mapfile -d ':' [array] < [file.txt]

$ mapfile [array] < <(ls)

mapfile [options] [array]

mapfile reads lines into a bash array. It's a bash builtin for array population.
The tool is also known as readarray. It efficiently reads files line by line into arrays.
mapfile reads lines into array.

ARRAY

Array variable name.

Maximum lines to read.

Lines to skip.

Remove trailing delimiters.

Use delimiter instead of newline.

Bash-specific builtin. Not available in sh. Alias is readarray.

mapfile was added to Bash 4.0 as a builtin for efficiently reading files into arrays.

readarray(1), read(1), bash(1)