Re: Help with BSD make

[Petar Bogdanovic <petar%smokva.net@localhost>]

On Sat, Jul 14, 2012 at 01:51:35PM +0200, tlaronde%polynum.com@localhost wrote:
> On Sat, Jul 14, 2012 at 01:40:17PM +0200, Petar Bogdanovic wrote:
> > On Sat, Jul 14, 2012 at 09:59:11AM +0100, Sad Clouds wrote:
> > > Hello, I'm learning make(1), so a bit of a daft question:
> > > 
> > > all: .PHONY
> > >   cd /tmp
> > >   pwd
> > > 
> > > This gives
> > > 
> > > cd /tmp
> > > make: exec(cd) failed (No such file or directory)
> > > *** Error code 1
> >[...] 
> >             -cd /foo \#
> >             # cd /foo \#
> >             # /bin/sh: line 0: cd: /foo: No such file or directory
> >             # *** Error code 1 (ignored)
> > 
> 
> Since the instruction block has no escaped newlines---i.e. the shell is
> supposed to treat one line after the other--- the cd(1) has no effect
> and can have no effect. It seems that make catches the error. To cd to
> /tmp AND have pwd print /tmp you have to escape or put everything on
> one line:

That's not really the issue here.  Besides, nbmake ``executes all
commands for a given target using a single shell invocation'' except
when -B was specified.  See make(1), COMPATIBILITY.

In the example above (cd /foo) make fails to execve a program called cd,
and does not execute any shell prior to that.  It also fails because of
the same reason when given two args (cd /foo /bar) but passes the lines
correctly to sh if one of the arguments contains a shell metacharacter
(like $ or #).

                Petar Bogdanovic