Finding all command resolutions | LPIC-1 101-500 Exam original practice question

103.1Basic

printf may be a shell builtin and an external executable.

List every resolution Bash can use for the name.

Assume there is no same-name alias or shell function.

Which command is appropriate?

Hint 1: Compare the lookup scope

Distinguish a list of every Bash candidate from one selected resolution or a filesystem location.

Hint 2: Key terms

Separate shell definitions, all candidates, and external paths.

type -a: Lists shell definitions and same-name executables on PATH instead of stopping at the first candidate.
command -v: Reports one result that the current shell would use to resolve the name.
Builtin and external executable: A Bash builtin and a file on disk can share the same command name.
which: Generally searches PATH for executable files; its behavior varies and does not guarantee every Bash resolution.

Detailed explanation

Incorrectwhich printf

Incorrect. which normally searches PATH and may omit shell builtins and alternate resolutions.

Finding an external printf does not also identify the Bash builtin. Separate where a file resides from whether all shell definitions were included.

Incorrectcommand -v printf

Incorrect. command -v reports one resolution, not all of them.

Under the stated premise, command -v printf reports printf as one resolution. It is useful for the selected result, but does not enumerate the same-name external file.

Incorrectwhereis printf

Incorrect. whereis searches files and manuals rather than Bash's full resolution order.

whereis locates related files rather than listing how the current Bash classifies and resolves a name.

Correcttype -a printf

Correct. type -a lists all resolutions known to Bash.

type with -a includes the builtin and the same-name executable on PATH. The verification deliberately supplies one external fixture and contrasts the list with command -v.

Try it yourself

An example you can run in a temporary verification environment.

LAB_DIR=$(mktemp -d) || exit 1
printf '#!/bin/sh\nexit 0\n' > "$LAB_DIR/printf"
chmod u+x "$LAB_DIR/printf" || exit 1
(
  export LC_ALL=C
  PATH="$LAB_DIR"
  hash -r
  LAB_ALL=$(type -a printf)
  builtin printf '%s\n' "${LAB_ALL//"$LAB_DIR"/<LAB_DIR>}"
  builtin printf 'first=%s\n' "$(command -v printf)"
)
rm -- "$LAB_DIR/printf"
rmdir -- "$LAB_DIR"

Official references

Expected result

printf is a shell builtin
printf is <LAB_DIR>/printf
first=printf

Key points

Bash builtins versus external commands
type -a
Why which is incomplete

Notes

Environment: Bash 5.2 / GNU coreutils in a fresh process without user startup files, with errexit off. Comparison PATH, LC_ALL, hash, alias and function settings stay in a subshell; HOME is unchanged.
Create one external fixture in a new temporary directory and restrict PATH only inside the subshell. The fixture is inspected rather than executed.
Only the temporary path in the actual type -a output is replaced by <LAB_DIR>. LC_ALL=C and the cleared command hash are confined to that subshell.

Foundation review

The basic case has two kinds of candidate

This question excludes aliases and same-name functions to focus on a builtin and an external executable. Defining an alias or function can add that definition to the list of candidates.

All candidates versus one selected result

type -a and command -v answer different questions. Both can inspect a name without running the external program.

Filesystem location is a different query

Locating a file with which or whereis does not establish that Bash builtin information was included.

Question IDKP-103-011

EnvironmentBash 5.2 / GNU coreutils in a fresh process without user startup files, with errexit off. Comparison PATH, LC_ALL, hash, alias and function settings stay in a subshell; HOME is unchanged.

Last technical review2026-11-04

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