djm@eng.umd.edu (David J. MacKenzie) (07/24/90)
In my last posting, I meant to say that the *SunOS* BSD ln -f allows hard links to directories, and that POSIX ln always unlinks existing destination files, unless -i is given, or the file is unwritable and -f is not given, in which cases it prompts you to allow you to skip the file. -- David J. MacKenzie <djm@eng.umd.edu> <djm@ai.mit.edu>
les@chinet.chi.il.us (Leslie Mikesell) (08/01/90)
In article <3797@auspex.auspex.com> guy@auspex.auspex.com (Guy Harris) writes: >Which means the ultimate problem isn't that one behavior is "good" and the >other is "bad", but that they're *different*. Standardizing on either >one would have worked (modulo windows opened by having to implement one >behavior with multiple commands on a system that provides the other). On systems without ln -f (where ln defaults to removing the target if it already exists) another program is required to perform a link which fails if the target exists. On SysVr[23] on 3B2's, this program exists as /etc/link: -r-x------ 1 root bin 1716 Mar 3 1988 /etc/link Thus, unless someone changes things there is no atomic file action that can be used by an ordinary user in a shell script. I'd call that "bad". Les Mikesell les@chinet.chi.il.us