Path: utzoo!utgpu!jarvis.csri.toronto.edu!rutgers!usc!apple!oliveb!tymix!tardis!jms From: jms@tardis.Tymnet.COM (Joe Smith) Newsgroups: comp.sys.amiga.tech Subject: Want multiple default directories Summary: Search other directories when Open() for reading fails Message-ID: <624@tardis.Tymnet.COM> Date: 25 Sep 89 05:06:03 GMT Reply-To: jms@tardis.Tymnet.COM (Joe Smith) Organization: McDonnell Douglas Field Service Co, San Jose CA Lines: 40 Here's a suggestion that would make toolpath unnecessary. It's an idea that is at least 12 years old on TOPS-10 that MS-DOS has only recently implemented. (And Unix doesn't have yet, as far as I know.) The idea is to have a directory (or list of directories) to be searched if a file is openned for input and not found in the current default directory. TOPS-10 called this the LIB PPN and/or the LIB: pathological device. MS-DOS 3.20 calls it the APPEND command. (I don't like that name.) The major difference between this idea and the current PATH is that PATH is for command/script files only, implemented in the CLI/SHELL, whereas the extended default directory would be implemented in the OS, available to all programs for any type of file. TOPS-10 has options as to what to do if the file is not found in the current directory but does exist in one of the alternate directories. They are: Open for Default Alternate ------- ------------- ---------------- reading return file found return "file not found" writing create new file supersede existing file update return error update file in other directory The other directories were searched whenever an attempt to lookup a file failed, even when an explicit directory path was provided on the open call. In Amiga terms, this would include attempts to find files in L:, DEVS:, and FONTS:, if desired. Workbench would benefit from this, by having a list of directories to search when locating the default tool when double-clicking an icon. What I am asking for would need to be integrated into the OS, not tacked on like the PATH: pseudo device. And, since a program could be loaded from any one of many directories, the OS would need to provide a call that would return the full path name of where the executable was really found. Ending on a humorous note, I can say "the other guys have it, we want it too!" -- Joe Smith (408)922-6220 | SMTP: JMS@F74.TYMNET.COM or jms@tymix.tymnet.com McDonnell Douglas FSCO | UUCP: ...!{ames,pyramid}!oliveb!tymix!tardis!jms PO Box 49019, MS-D21 | PDP-10 support: My car's license plate is "POPJ P," San Jose, CA 95161-9019 | narrator.device: "I didn't say that, my Amiga did!"