Which command is use to show a list of all files where name starts with either a B or C in the current directory?

How to get the list of files in a directory in a shell script?

In addition to the most-upvoted answer by @Ignacio Vazquez-Abrams, consider the following solutions which also all work, depending on what you are trying to do. Note that you can replace "path/to/some/dir" with . in order to search in the current directory.

1. List different types of files using find and ls

References:

1. For find, see this answer. See also my comment here.
2. For ls, see linuxhandbook.com: How to List Only Directories in Linux

Tip: for any of the find examples below, you can pipe the output to sort -V if you'd like it sorted.

Example:

find . -maxdepth 1 -type f | sort -V

List only regular files [-type f] 1 level deep:

# General form find "path/to/some/dir" -maxdepth 1 -type f # In current directory find . -maxdepth 1 -type f

List only symbolic links [-type l] 1 level deep:

# General form find "path/to/some/dir" -maxdepth 1 -type l # In current directory find . -maxdepth 1 -type l

List only directories [-type d] 1 level deep:

Note that for the find example here, we also add -mindepth 1 in order to exclude the current directory, ., which would be printed as . at the top of the directory list otherwise. See here: How to exclude this / current / dot folder from find "type d"

# General form find "path/to/some/dir" -mindepth 1 -maxdepth 1 -type d # In current directory find . -mindepth 1 -maxdepth 1 -type d # OR, using `ls`: ls -d

Combine some of the above: list only regular files and symbolic links [-type f,l] 1 level deep:

Use a comma [,] to separate arguments to -type:

# General form find "path/to/some/dir" -maxdepth 1 -type f,l # In current directory find . -maxdepth 1 -type f,l

2. Capture the output of any command into a bash indexed array, with elements separated by the newline char [\n]

However, $search_dir contains many files with whitespaces in their names. In that case, this script does not run as expected.

This is solved by telling bash to separate elements in the string based on the newline char \n instead of the space char--which is the default IFS [Internal Field Separator--see The Meaning of IFS in Bash Scripting] variable used by bash. To do this, I recommend using the mapfile command.

The bash script static code analyzer tool named shellscript recommends using mapfile or read -r whenever you want to read in a string into a bash array, separating elements based on the newline char [\n]. See: //github.com/koalaman/shellcheck/wiki/SC2206.

Update: to see examples of how to do this with both mapfile and read -r see my answer here: How to read a multi-line string into a regular bash "indexed" array. I now prefer to use read -r instead of mapfile, because mapfile will KEEP any empty lines as elements in the array, if any exist, which I do NOT want, whereas read -r [again, my preference now] will NOT keep empty lines as elements in the array.

[Back to my original answer:]

Here is how to convert a newline-separated string into a regular bash "indexed" array with the mapfile command.

# Capture the output of `ls -1` into a regular bash "indexed" array. # - includes both files AND directories! mapfile -t allfilenames_array