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Is cd command is a built-in function or a script

+2 votes
471 views

We all know that cd is a built-in function of whatever shell you're using.

$ cat /usr/bin/cd
#!/bin/sh
builtin cd "$@"

Does anybody know why this file exists?

posted Sep 12, 2013 by Sheetal Chauhan

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2 Answers

+1 vote

I believe it's a backwards-compatibility thing. IIRC, System7's Bourne shell didn't have a built-in "cd" command (or several others). Some scripts probably still look for that file (and the others).

It's been superfluous for a long time, but time has proven that when you take away something like that, eventually something breaks or someone gripes about it.

answer Sep 12, 2013 by Jai Prakash
No. "cd" has always been a builtin; it does not work otherwise. Think it through.
commented Sep 12, 2013 by Seema Siddique
0 votes 
~]$ cat /usr/bin/cd
cat: /usr/bin/cd: No such file or directory

~]$ which cd
/usr/bin/which: no cd in
(/usr/lib64/qt-3.3/bin:/usr/lib64/ccache:/usr/local/bin:/usr/bin:/bin:/usr/local/sbin:/usr/sbin:/home/tim/.local/bin:/home/tim/bin)
answer Sep 12, 2013 by Meenal Mishra
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