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RE: /usr/bin/cd??
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RE: /usr/bin/cd??



> New in 10.4: Something called "/usr/bin/cd"; no man page, it's a
> 1-line, quite obscure, shell command.
>
> If I use a 'cd' in a ".term" command, that shell file gets
> executed, in
> place of the built-in 'change directory' command.
>
> Can anyone spare a clue as to what it's all about?

I'm going on some old memories here, so I cannot provide a very
detailed explanation, but the reason /usr/bin/cd exists is due
to a POSIX requirement that relates to aliases and being able to
not use an alias via escaping.  But /usr/bin/cd is a useless
script since if you run cd within a shell script the directory
change only applies to the subshell under which the script runs.
cd cannot be a shell script.

Also, the script is a generic script in that it is used for a
number of commands and not just cd.

I noticed that /usr/bin/cd has a hard link count of 15 on my
10.4 system.  So I looked at the inode number for /usr/bin/cd
(run 'ls -i /usr/bin/cd') and then ran
find /usr/bin -inum number_from_ls -print

All of these are the same script
$ find /usr/bin -inum 51616 -print
/usr/bin/alias
/usr/bin/bg
/usr/bin/cd
/usr/bin/command
/usr/bin/fc
/usr/bin/fg
/usr/bin/getopts
/usr/bin/hash
/usr/bin/jobs
/usr/bin/read
/usr/bin/type
/usr/bin/ulimit
/usr/bin/umask
/usr/bin/unalias
/usr/bin/wait

-Preston

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References: 
 >/usr/bin/cd?? (From: Justin Walker <email@hidden>)



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