Bug 21990

The exec(3) manpage states that the exec?p functions fall back to
a search path of "/bin:/usr/bin:" in the absense of a "/" in
argv[0] as well as a "PATH" variable.  This is quite a difference
from the "/bin:/usr/bin" path that actually applies.

Fix: 

Not sure about it due to further reading in the manpage:
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...
COMPATIBILITY
     Historically, the default path for the execlp() and execvp() functions
     was ``:/bin:/usr/bin''. This was changed to place the current directory
     last to enhance system security.
...
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Either the source or the doc is wrong in this respect.  As I'm
not sure, there's no patch to be included here.  Although I like
the current behaviour very much to *not* include the current
directory when not explicitely specified in the PATH variable
(and those who do get what they deserve ...).  So I feel the
manpage to be behind the established situation.  Please don't
tell me the source is. :)


virtually yours   82D1 9B9C 01DC 4FB4 D7B4  61BE 3F49 4F77 72DE DA76
Gerhard Sittig   true | mail -s "get gpg key" Gerhard.Sittig@gmx.net
-- 
     If you don't understand or are scared by any of the above
             ask your parents or an adult to help you.
How-To-Repeat: 
~/FreeBSD-source $ find \
src-current/lib/libc src-current/include \
src-stable/lib/libc src-stable/include \
-type f -print0 | xargs -0 grep -w _PATH_DEFPATH /dev/null
src-current/lib/libc/gen/exec.c:                path = _PATH_DEFPATH;
src-current/include/paths.h:#define     _PATH_DEFPATH   "/usr/bin:/bin"
src-stable/lib/libc/gen/exec.c:         path = _PATH_DEFPATH;
src-stable/include/paths.h:#define      _PATH_DEFPATH   "/usr/bin:/bin"

man 3 execvp (on a -STABLE machine)
-----------------------------------------------------------------
...
The functions execlp() and execvp() will duplicate the actions of the
shell in searching for an executable file if the specified file name does
not contain a slash ``/'' character.  The search path is the path speci-
fied in the environment by ``PATH'' variable.  If this variable isn't
specified, the default path ``/bin:/usr/bin:'' is used.  In addition,
certain errors are treated specially.
...
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