From mboxrd@z Thu Jan 1 00:00:00 1970 From: paul.winalski@gmail.com (Paul Winalski) Date: Tue, 28 Nov 2017 14:36:21 -0500 Subject: [TUHS] Dash options In-Reply-To: References: <201711280551.vAS5pDZt014974@darkstar.fourwinds.com> Message-ID: On 11/28/17, Andrew Warkentin wrote: > > Multics had dash options, so that's presumably where Unix got them > from. I believe slash options were mostly a DEC thing that DOS and its > successors borrowed (I think they originated in TOPS-10). That's how I remember it. I think slash was chosen because it looks somewhat like a toggle switch. MS/DOS patterned its command line syntax after RT-11 and inherited the slash as a command option introduction from there. Unfortunately this meant that they couldn't use slash as a directory separator when they got a hierarchical file system, and so they chose backslash instead. Nowadays the Windows shell, and I think also the underlying image activation system service, use an ugly algorithmic hack to support both directions of slashes in file pathnames. -Paul W.