On 19 Feb 2006 at 2:16, A-NO-NE Music wrote: > Ken Moore / 2006/02/18 / 05:06 PM wrote: > > >I never met that outside the context of an OS command line interface. > > Isn't it confined to UNIX? I see that in MS DOS the ">" character is > > called "pipe", because it performs the same function as the UNIX > >"|". > > I don't think so. > In DOS prompt, 'dir | more', it's a PIPE as long as I remember. Of > course DOS was a Unix CUI wannabe :-)
I honestly don't think DOS has any direct "genetic" relation to Unix CLI in its design, except perhaps through Q-DOS (the product that Microsoft purchased), which was something of a knock-off of CPM, another personal computer OS from the late 70s. A commandline interface was the only interface to any OS before the widespread use of a GUI, so any OS would have had it at that time. Since OS's all have a number of things in common in terms of tasks that a user needs to perform, all CLI's are going to be pretty much equivalent in the functionality they provide (insofar as the different OS's support those features; DOS lacked a lot of things that Unix, even the Unix of the late 70s, offered). Given how different the command names are in DOS, I don't see any real direct line back to Unix at all, expecially given that many of the functions are not mapped one-to-one onto the differently-named-but-equivalent commands. > I believe both DOS and U/Linux reserves '>' char for output. I am familiar with referring to the > as a redirector, as in: copy c:\*.* d:\ >copy.txt That redirects the console output of the copy command to the file "copy.txt". copy c:\*.* d:\ >>copy.txt The doubling up appends the output to any existing file (as opposed to creating the file anew each time, replacing any existing file bythat name), or creates the file for the first time. The other symbol, <, can also be used, to redirect output into a command. I can't remember an example of that, as it was a fairly exotic thing to attempt back when I was a wiz at writing DOS files. The pipe symbol, |, (and yes, that's the term I've always used for it among geeks, but use the term "vertical bar" when dealing with non- geeks; it's a useful character for use in constructing hard-to-crack passwords) is for redirecting output between programs, as in: dir *.* | more That take the output of the directory listing command and pipes it through the "more" program, which splits the output into screens and puts a "--more--" at the end, to, I guess, suggest that you strike the spacebar to get the next screen. I never realized it, but there are only a few keystrokes that MORE responds to (these are outlined in the help for it, reached at the command prompt by typing "more /?"). Of course, I'm not really checking DOS, but the NT command prompt. However, the NT command prompt is, so far as I know, 100% backwardly compatible with DOS, though many commands have expanded functionality. But so far as I can see, the behaviors of |, > and < have not been changed. -- David W. Fenton http://dfenton.com David Fenton Associates http://dfenton.com/DFA/ _______________________________________________ Finale mailing list Finale@shsu.edu http://lists.shsu.edu/mailman/listinfo/finale
