>From XRAT A.8.3, the value is advisory, and need not be a directly resolvable path by means the standard provides. What constitutes a valid value for a platform should be documented, and I'd see making that a requirement, as to what applies to the utilities it provides that make use of the variable.
On Monday, June 26, 2017 Vincent Lefevre <vincent-o...@vinc17.net> wrote: In Issue 7, 2016 Edition, Section 8.3 "Other Environment Variables", page 178, line 5864: SHELL This variable shall represent a pathname of the user's preferred command language interpreter. [...] This is ambiguous, as it does not exclude a relative pathname, and doesn't say how it is resolved in the latter case (e.g. using $PATH or not). At least OpenSSH does not use $PATH. So, I assume that POSIX should explicitly require that SHELL be an absolute pathname. At the same time, in 2.5.2 "Special Parameters", page 2351, line 74887, it should be said that $0 is not necessarily an absolute pathname. Thus something like SHELL=$0 is incorrect. -- Vincent Lefèvre <vinc...@vinc17.net> - Web: <https://www.vinc17.net/> 100% accessible validated (X)HTML - Blog: <https://www.vinc17.net/blog/> Work: CR INRIA - computer arithmetic / AriC project (LIP, ENS-Lyon)