NetNews Usenet Archive 1993 #3/NN_1993_3.iso/spool/comp/unix/shell/5456

Text File | 1993-01-21 | 2.8 KB | 62 lines

Newsgroups: comp.unix.shell
Path: sparky!uunet!panther!mothost!white!rtsg.mot.com!motcid!yorton
From: [e-mail] (James J. Yorton)
Subject: Korn's Response - ksh autoload quirk
Message-ID: <[e-mail]>
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Organization: Motorola Inc., Cellular Infrastructure Group
Date: Thu, 21 Jan 1993 23:15:31 GMT
Lines: 49

At one time, someone questioned the ksh autoload feature.
I passed the question onto David Korn who responded.
Below is a copy of the original post.  Following it is Korn's
response to me.  Note that his response contains an explanation
of how ksh-92 will handle this.

In comp.unix.shell [e-mail] wrote:

> ksh 11/16/88d under Dell SVR4 4.0 here on ddsw1 and the ksh running
> on a 3B2 on gagme recognize any filename in a directory in $FPATH as
> an undefined function whether or not that name has been declared for
> autoload with "autoload" or "typeset -fu."
>
> But there is a difference when a file in $FPATH has the same name as
> an executable file in $PATH.  If the undefined function has been
> formally declared with "autoload" or "typeset -fu," then ksh
> interprets an appearance of that name on the command line as a
> reference to the function.  If the undefined function has not been
> declared but is recognized as such solely by dint of lying in
> $FPATH, then an appearance of the name on the command line is taken
> by ksh parser to mean the executable in $PATH (unless the function
> has actually been loaded with the . command or by a call to another
> function in the same file to whose name the file is linked).
>
> Is that the correct behavior?  Is a file name in $FPATH that hasn't
> been declared for autoload supposed to be recognizable at all as an
> undefined function?  I haven't seen anything about that (nor about a
> difference in precedence from a declared undefined function) in the
> ferkakte manual.


David Korn writes:

: The way ksh88 works, is that PATH is searched first and then FPATH.
: The autoload feature allows functions bindings to occur before PATH.
:
: ksh92 uses a different strategy.  While searching PATH, if a directory
: is found that is also in FPATH, the the file is processed as a function.
: This allows the user control over the order of function directories
: and regular directories.  In the case the PATH and FPATH contain
: disjoint directories, the result is the same.


--------------------------------------+---------------------------------------
Jim Yorton                            | Telephone:  [phone]
Motorola Inc., General Systems Sector |
Cellular Infrastructure Group         | internet:  [e-mail]
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