On Fri, Mar 12, 2010 at 12:15 PM, Ken Irving <ken.irv...@alaska.edu> wrote:
> On Fri, Mar 12, 2010 at 11:57:41AM +0200, Pierre Gaston wrote: > > On Fri, Mar 12, 2010 at 11:50 AM, Ken Irving <ken.irv...@alaska.edu> > wrote: > > > > > On Fri, Mar 12, 2010 at 09:16:05AM +0000, Marc Herbert wrote: > > > > >> Could this sentence: > > > > >> > > > > >> "An interactive shell is one started without non-option arguments, > > > > >> unless -sis specified, without specifying the > > > > >> -c option, and whose input and error output are both connected to > > > terminals > > > > >> (as determined by isatty(3)), or one started with the -i option. " > > > > >> > > > > >> be any more confusing? > > > > > > > > > > Is seems pretty clearly stated to me. > > > > > > > > Please enlighten us with the priority of English boolean operators. > > > > > > > > I have never seen a natural language sentence with so many boolean > > > operators. > > > > > > Well I can try. > > > > > > An interactive shell is one started without non-option arguments, > > > > > > If there are any arguments then they must be options... > > > > > > unless -s is specified, > > > > > > bash(1) says: "If the -s option is present ... then commands are read > > > from the standard input", which clearly is not interactive. > > > > > > > If you run "bash -s foo bar" in a terminal it starts an interactive > shell. > > Maybe the definition isn't correct, then, if your example is at odds > with the first two statements. The -s is accompanied by foo, and bar > is a non-option argument. I would think that 'foo' would executed as > a command, and the the file bar would be run as a script; I don't see > how this would be interactive, though. > > Ken > The definition is correct but maybe not too clear. "unless -s is specified" means that the first rule is true unless you use -s ie you can include non option argument if you use -s and still have an interactive shell, so bash -s foo bar is interactive (if connected to a terminal) In fact this clearly stated in the ref manual "The -s invocation option may be used to set the positional parameters when an interactive shell is started." The role played by -c is the definition is less clear to me since with -c you must give a non option argument and thus the "non-interactivity" is probably covered by the first rule and I don't think you can use both -s and -c at the same time. (well you can put both but the first one to appear disables the parsing of the second one)
