[Date Prev][Date Next] [Thread Prev][Thread Next] [Date Index] [Thread Index]

Re: Definition of alphanumeric?



Manoj Srivastava <srivasta@debian.org> writes:

> 	So, what is the provenance of this CURDIR variable? Has it
>  been blessed by POSIX? indeed not. However, I see that both $PWD and
>  the pwd utility are sanctioned by POSIX; so for maximal portability
>  scripts should *NOT* use  CURDIR, the should either use PWD, or call
>  pwd themselves, like the example did.

The days when running "pwd" was moderately expensive are long past,
and since PWD can be wrong sometimes, I would suggest every script
that wants the anwser should use "pwd".

Shell script programming is *hard*, because even that is not often
what you want.  A shell script should normally continue to work right
if parent directories are changed; converting things to absolute paths
and then using that is frequently a source of gratuitous bugs in this
area.

Thomas



Reply to: