17 Jan
2011
17 Jan
'11
1:19 a.m.
John Cowan wrote:
How'd you get the impression? I can't verify this.
bash-1.05:execute_cmd.c executed the commands itself, in a subshell,
" [ errno == ENOEXEC ]
/* This file is executable.
If it begins with #!, then help out people with losing
operating systems. Otherwise, check to see if it is a binary
file by seeing if the first line (or upto 30 characters) are in
the ASCII set. Execute the contents as shell commands. */ "
and this hasn't been changed (except length or return status)
until the current release.
Perhaps you had another shell in mind? I believe a shell should
try to execute commands itself instead of calling any other shell.
(That's the only way how executing on in POSIX shell is possible, BTW,
because neither #! nor paths are standardized).
Sven Mascheck scripsit:
This doesn't sound obligatory to me (I know it's academic).
DMR might have known the csh-hack (and if a comment character is
implemented anywhere, here csh, then it's obvious to use it for #!)
As you mention "shebangs began .. as
csh-only hack":
I still wonder if one may call the BSD csh-hack as origin,
because #! might have been developed independently at Bell Labs.
No, that would be too much of a coincidence to choose exactly the
same characters. There has to be a single point of origin, from
which it spread by stimulus diffusion (you hear there are telescopes,
you know they use lenses, you build your own telescope). I thought
sh-like shells in general try to interprete scripts themselves
upon an ENOEXEC. Do you know certain shells which actually call "/bin/sh"?
Yes, seemingly bash does that too. Bogus.