Russ Allbery <[EMAIL PROTECTED]> writes: > Manoj Srivastava <[EMAIL PROTECTED]> writes:
>> This flows from the Release policy. Not specifying /bin/bash >> in scripts is not considered a RC bug. > I can try to propose better language for this. I think that using pure > bash-specific constructs not found in dash in /bin/sh scripts should > actually be an RC bug, but using test -a or test -o should not. I think > we need to say that /bin/sh scripts are permitted to use POSIX shell > capabilities plus a short list of additional capabilities that > everything other than posh also implement. Here's a proposed patch. What do people think about this approach? I know there was an inconclusive Policy discussion a while back about how best to deal with this issue. As you can tell from this patch, I favor the approach of documenting the specific features that we require and assuming that their semantics are sufficiently clear in practice. This patch would resolve Policy bug #294962 as well. --- orig/policy.sgml +++ mod/policy.sgml @@ -6727,25 +6727,34 @@ <p> The standard shell interpreter <file>/bin/sh</file> can be a - symbolic link to any POSIX compatible shell, if <tt>echo - -n</tt> does not generate a newline.<footnote> - Debian policy specifies POSIX behavior for - <file>/bin/sh</file>, but <tt>echo -n</tt> has widespread - use in the Linux community (in particular including this - policy, the Linux kernel source, many Debian scripts, - etc.). This <tt>echo -n</tt> mechanism is valid but not - required under POSIX, hence this explicit addition. - Also, rumour has it that this shall be mandated under - the LSB anyway. - </footnote> + symbolic link to any POSIX compatible shell provided that it + supports the following additional features not mandated by + POSIX: + <list> + <item><tt>echo -n</tt> must not generate a newline<footnote> + Debian policy specifies POSIX behavior for + <file>/bin/sh</file>, but <tt>echo -n</tt> has widespread + use in the Linux community (in particular including this + policy, the Linux kernel source, many Debian scripts, + etc.). This <tt>echo -n</tt> mechanism is valid but not + required under POSIX, hence this explicit addition. Also, + rumour has it that this shall be mandated under the LSB + anyway. + </footnote> + </item> + <item>the <tt>-a</tt> and <tt>-o</tt> <tt>test</tt> operators + must be supported</item> + <item><tt>local</tt> to create a scoped variable must be + supported</item> + </list> Thus, shell scripts specifying <file>/bin/sh</file> as - interpreter must only use POSIX features. If a script - requires non-POSIX features from the shell interpreter, the - appropriate shell must be specified in the first line of the - script (e.g., <tt>#!/bin/bash</tt>) and the package must - depend on the package providing the shell (unless the shell - package is marked "Essential", as in the case of - <prgn>bash</prgn>). + interpreter must only use POSIX features or features guaranteed + by the above list. If a script requires other non-POSIX features + from the shell interpreter, the appropriate shell must be + specified in the first line of the script (e.g., + <tt>#!/bin/bash</tt>) and the package must depend on the package + providing the shell (unless the shell package is marked + "Essential", as in the case of <prgn>bash</prgn>). </p> <p> -- Russ Allbery ([EMAIL PROTECTED]) <http://www.eyrie.org/~eagle/> -- To UNSUBSCRIBE, email to [EMAIL PROTECTED] with a subject of "unsubscribe". Trouble? Contact [EMAIL PROTECTED]