From: Bakul Shah
Use of "flag" for this purpose seems
strange. "option" makes more sense.
People on this list seem to forget that there were computers before UNIX.
The _syntax_ of "-f" probably predates any UNIX; Multics used it extensively.
See the "Introduction to Multics", MAC-TR-123, January 1974 (a little after
UNIX V1, but I expect I could probably track it back further in time, if I
cared to put in the effort); pg. 3-24.
Interestingly, I looked though the CTSS manual, and CTSS did not seem to use
this syntax for flag arguments: see, e.g., the SAVE command (section AH.3.03).
The _name_ "flag" came in early on UNIX. (Multics called them
"arguments";
see above, pg. 3-27, top line.) We can see this happen - see:
http://squoze.net/UNIX/v1man/man1/du
which calls the "-a" and "-s" "arguments"; but in:
http://squoze.net/UNIX/v1man/man1/ld
"-s", "-u", etc are called "flag arguments".
Long enough ago that certainty about the etymology/rationale is probably now
lost.
Noel