diff options
Diffstat (limited to 'vms/perlvms.pod')
| -rw-r--r-- | vms/perlvms.pod | 16 |
1 files changed, 12 insertions, 4 deletions
diff --git a/vms/perlvms.pod b/vms/perlvms.pod index 56f66497d8..1705bf882f 100644 --- a/vms/perlvms.pod +++ b/vms/perlvms.pod @@ -715,17 +715,24 @@ that F<PERL_ENV_TABLES> is set up so that the logical name C<story> is found, rather than a CLI symbol or CRTL C<environ> element with the same name. -When an element of C<%ENV> is set to a non-empty string, the +When an element of C<%ENV> is set to a defined string, the corresponding definition is made in the location to which the first translation of F<PERL_ENV_TABLES> points. If this causes a logical name to be created, it is defined in supervisor mode. +(The same is done if an existing logical name was defined in +executive or kernel mode; an existing user or supervisor mode +logical name is reset to the new value.) If the value is an empty +string, the logical name's translation is defined as a single NUL +(ASCII 00) character, since a logical name cannot translate to a +zero-length string. (This restriction does not apply to CLI symbols +or CRTL C<environ> values; they are set to the empty string.) An element of the CRTL C<environ> array can be set only if your copy of Perl knows about the CRTL's C<setenv()> function. (This is present only in some versions of the DECCRTL; check C<$Config{d_setenv}> to see whether your copy of Perl was built with a CRTL that has this function.) -When an element of C<%ENV> is set to an empty string or C<undef>, +When an element of C<%ENV> is set to C<undef>, the element is looked up as if it were being read, and if it is found, it is deleted. (An item "deleted" from the CRTL C<environ> array is set to the empty string; this can only be done if your @@ -734,8 +741,9 @@ C<delete> to remove an element from C<%ENV> has a similar effect, but after the element is deleted, another attempt is made to look up the element, so an inner-mode logical name or a name in another location will replace the logical name just deleted. -It is not possible at present to define a search list logical name -via %ENV. +In either case, only the first value found searching PERL_ENV_TABLES +is altered. It is not possible at present to define a search list +logical name via %ENV. The element C<$ENV{DEFAULT}> is special: when read, it returns Perl's current default device and directory, and when set, it |