Changing to your home directory in Unix shells Which command returns the current shell to the user's home directory using the standard POSIX behavior?
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Acd..
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Bcd/
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Ccd
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Dcd HOME.
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ENone of the above
Answer
Correct Answer: cd
Explanation
Introduction / Context:Navigating directories is a daily task in Unix/Linux. Returning quickly to your home directory saves time. The POSIX standard defines a simple way to do this that works across Bourne-like shells (sh, bash, ksh, dash).
Given Data / Assumptions:
- We are in a POSIX-compatible shell.
- HOME environment variable is set to the user's home path.
- No shell options have altered the default
cdbehavior.
Concept / Approach:
Running cd with no arguments changes the current directory to $HOME. This is standardized, portable, and works consistently. Alternative shortcuts like cd ~ also work in many shells due to tilde expansion, but the canonical minimal form is bare cd.
Step-by-Step Solution:
Check current directory withpwd.Execute cd with no arguments.Verify new location with pwd, which should equal $HOME.Optionally use echo $HOME to see the target path.Verification / Alternative check:
Try cd ~ as an alternative in bash/ksh/zsh; it should produce the same result. Using cd - will toggle back to the previous directory if needed.
Why Other Options Are Wrong:
- cd..: invalid; correct usage is
cd ..(with space) to go up one level, not to home. - cd/: goes to the filesystem root
/, not the home directory. - cd HOME.: not valid syntax;
HOMEis an environment variable and would require expansion likecd "$HOME". - None of the above: incorrect because
cdis correct.
Common Pitfalls:
Confusing root directory with home; forgetting quotes when $HOME contains spaces; assuming cd.. (DOS style) works on Unix shells.
Final Answer:
cd