UNIX for Dummies Questions & Answers

Indeed, but as long as this is documented, that's no problem to me. I wouldn't say the pwd builtin behaves incorrectly. It behaves as designed and documented. i.e. it prints PWD value. i.e. the variable storing the current directory set by the last "cd". If you want to get a symlink free pwd, you can use "pwd -P" which is POSIX. see pwd
About HP-UX implementation, the posted "cd" code has a useless "exit $?" last line.

By the way, (very) early Unix shell implementations had no builtins and all utilities were external commands, including cd which was spelled chdir or ch at that time. When the fork system call was first implemented, the chdir command ceased to work puzzling Dennis Ritchie and team.

cf: Early Unix history and evolution (looks for "memorable")

My view on the changed behaviour of builtin "pwd" is based on extensive experience of cross-platform porting/development and some of the subtle differences you encounter.
Personally I prefer "pwd" to show the current working directory. Maybe I'm being picky?

Some of it is of course nostalgia for some of the older rock-steady unix implementations which were ONE version of unix. i.e. Not hybrid Berkeley and System V and whatever.

The sheer number of posts on this board which work on the posters computer but do not work on the original posters computer is evidence that the latest POSIX "standard" is yet again a joke. The POSIX saga has been going on for umpteen years.

Imho. While major manufacturers such as IBM, HP and Sun continue to produce manufacture-specific unix commands for basic functions there is no chance of a common unix standard. I cite virtually any command to do with hardware configuration or software libraries.

@jlliagre
Great link. Very interesting. Big nostalgia for me because after working on huge impersonal Mainframe computers I worked on PDP-11/23 and VAX. However we ran RSX11-M on the PDP's and eventually offered developers the DCL command interface which was also available as an interface to VMS on the VAX's.
Hmm. Some of the command syntax in DCL is remarkably similar to subsequent DRDOS and MSDOS. Must be a coincidence.
For those who were born before POSIX, here is a weak article about an early standard command language.
DIGITAL Command Language - Wikipedia, the free encyclopedia
Omg. Apart from space characters around "=" many unix users will be able to follow the syntax.

Before symlinks were introduced in Unix, the current directory notion was unambiguous. Afterward, not any more.

One can argue the following behavior might be surprising to someone unaware about the fact /a/b is a symbolic link.

Code:

$ cd /a/b
$ pwd
/c/d

In any case, both /a/b and /c/d are both a valid path to the same directory.