basename throws error when a wildcard is specified

Question

I want to get the filename from a file path. It works fine when one file is specified, such as:

fname=$(basename -- /tmp/file1)

However, if provided as an expression such as fname=$(basename -- /tmp/fi*) it throws basename: extra operand ‘/tmp/file1’.

In above case I don't expect it to resolve and expand the expression but rather just return fi* in fname, is it possible to do it using basename?

Answer 1

As stated in comments; the basename command only provides base name for an individual file. If you need to collect base name from multiple files matching a wildcard * pattern, then you need to either work with arrays, or iterate the globbing pattern matches:

With Bash arrays:

#!/usr/bin/env bash

# Populates the files array with the wildcard pattern glob expansion
files=(/tmp/fi*)

# Strip each individual file names starting with anything and up to last /
# stores the results into another basenames array
basenames=("${files[@]##*/}")

# Iterate the basenames array to work with
for abasename in "${basenames[@]}"; do
  : do something with each "$abasename"
done

Now if the shell you use has no support for arrays, you may iterate directly and process base names one by one:

#!/bin/sh

for afile in /tmp/fi*; do

  # strip the directory path to get basename
  abasename="${afile##*/}"

  : do something with that "$abasename"
done

Answer 2

If you do not want to expand the expression add quotes around it.

fname=$(basename -- "/tmp/fi*")

Answer 3

temporarily disable globbing

fname=$(set -o noglob; basename /tmp/fi*)

note fname will contain the string "fi*"