On Fri, May 7, 2010 at 10:41 AM, Eric Blake <ebl...@redhat.com> wrote: > On 05/07/2010 09:31 AM, Peng Yu wrote: >> On Fri, May 7, 2010 at 10:16 AM, Eric Blake <ebl...@redhat.com> wrote: >>> On 05/07/2010 09:02 AM, Peng Yu wrote: >>>> Suppose I need to modify one primary file slightly to do something a >>>> little bit different. But I still need to do the original job, >>>> therefore I need to keep it the original M files. I can copy the whole >>>> directory and then modify one file in the newly copied N files. But >>>> I'll lose track of which file has been changed later on, which is >>>> important to me. >>> >>> Consider using a version control system. Track the contents of your >>> directory under your favorite VCS, like git, and then you can use >>> version control commands to generate the delta for both primary and >>> secondary files across any state that you committed. >> >> I can't use version control for >> 1. I need to frequently change file names. >> 2. Both primary and secondary files could be of hundred of MB or even GB. > > git handles both of those situations, without too much hassle. > >>> But overloading bash's > and >> operators is not possible. >> >> Is it because the underlying library that used in bash doesn't support >> the semantic of symbolic link that I propose? Or it is because of the >> OS? >> >> Is it possible to modify source code of bash to change the semantics >> of symbolic link. > > Yes, it's possible to modify the source of bash to change how bash > treats symlinks when using the > operator. But I would advise against > it, as your fork of bash would no longer comply with POSIX, and would > probably break a lot more than it fixes. Rather, if you insist on > modifying bash, consider adding a new operator (maybe spelled '>;', > similar to the noclobber override spelling of '>|'), so that your use of > the new operator is explicit that you know what you are doing in your > scripts (if the operand of the new operator is a symlink, break the > symlink and create a file in its place instead of operating on the > target of the symlink).
Is there a way to define the operator '>;' without touching the bash source code? -- Regards, Peng
