.\" Automatically generated by Pod::Man v1.34, Pod::Parser v1.13
.\"
.\" Standard preamble:
.\" ========================================================================
.de Sh \" Subsection heading
.br
.if t .Sp
.ne 5
.PP
\fB\\$1\fR
.PP
..
.de Sp \" Vertical space (when we can't use .PP)
.if t .sp .5v
.if n .sp
..
.de Vb \" Begin verbatim text
.ft CW
.nf
.ne \\$1
..
.de Ve \" End verbatim text
.ft R
.fi
..
.\" Set up some character translations and predefined strings. \*(-- will
.\" give an unbreakable dash, \*(PI will give pi, \*(L" will give a left
.\" double quote, and \*(R" will give a right double quote. | will give a
.\" real vertical bar. \*(C+ will give a nicer C++. Capital omega is used to
.\" do unbreakable dashes and therefore won't be available. \*(C` and \*(C'
.\" expand to `' in nroff, nothing in troff, for use with C<>.
.tr \(*W-|\(bv\*(Tr
.ds C+ C\v'-.1v'\h'-1p'\s-2+\h'-1p'+\s0\v'.1v'\h'-1p'
.ie n \{\
. ds -- \(*W-
. ds PI pi
. if (\n(.H=4u)&(1m=24u) .ds -- \(*W\h'-12u'\(*W\h'-12u'-\" diablo 10 pitch
. if (\n(.H=4u)&(1m=20u) .ds -- \(*W\h'-12u'\(*W\h'-8u'-\" diablo 12 pitch
. ds L" ""
. ds R" ""
. ds C` ""
. ds C' ""
'br\}
.el\{\
. ds -- \|\(em\|
. ds PI \(*p
. ds L" ``
. ds R" ''
'br\}
.\"
.\" If the F register is turned on, we'll generate index entries on stderr for
.\" titles (.TH), headers (.SH), subsections (.Sh), items (.Ip), and index
.\" entries marked with X<> in POD. Of course, you'll have to process the
.\" output yourself in some meaningful fashion.
.if \nF \{\
. de IX
. tm Index:\\$1\t\\n%\t"\\$2"
..
. nr % 0
. rr F
.\}
.\"
.\" For nroff, turn off justification. Always turn off hyphenation; it makes
.\" way too many mistakes in technical documents.
.hy 0
.if n .na
.\"
.\" Accent mark definitions (@(#)ms.acc 1.5 88/02/08 SMI; from UCB 4.2).
.\" Fear. Run. Save yourself. No user-serviceable parts.
. \" fudge factors for nroff and troff
.if n \{\
. ds #H 0
. ds #V .8m
. ds #F .3m
. ds #[ \f1
. ds #] \fP
.\}
.if t \{\
. ds #H ((1u-(\\\\n(.fu%2u))*.13m)
. ds #V .6m
. ds #F 0
. ds #[ \&
. ds #] \&
.\}
. \" simple accents for nroff and troff
.if n \{\
. ds ' \&
. ds ` \&
. ds ^ \&
. ds , \&
. ds ~ ~
. ds /
.\}
.if t \{\
. ds ' \\k:\h'-(\\n(.wu*8/10-\*(#H)'\'\h"|\\n:u"
. ds ` \\k:\h'-(\\n(.wu*8/10-\*(#H)'\`\h'|\\n:u'
. ds ^ \\k:\h'-(\\n(.wu*10/11-\*(#H)'^\h'|\\n:u'
. ds , \\k:\h'-(\\n(.wu*8/10)',\h'|\\n:u'
. ds ~ \\k:\h'-(\\n(.wu-\*(#H-.1m)'~\h'|\\n:u'
. ds / \\k:\h'-(\\n(.wu*8/10-\*(#H)'\z\(sl\h'|\\n:u'
.\}
. \" troff and (daisy-wheel) nroff accents
.ds : \\k:\h'-(\\n(.wu*8/10-\*(#H+.1m+\*(#F)'\v'-\*(#V'\z.\h'.2m+\*(#F'.\h'|\\n:u'\v'\*(#V'
.ds 8 \h'\*(#H'\(*b\h'-\*(#H'
.ds o \\k:\h'-(\\n(.wu+\w'\(de'u-\*(#H)/2u'\v'-.3n'\*(#[\z\(de\v'.3n'\h'|\\n:u'\*(#]
.ds d- \h'\*(#H'\(pd\h'-\w'~'u'\v'-.25m'\f2\(hy\fP\v'.25m'\h'-\*(#H'
.ds D- D\\k:\h'-\w'D'u'\v'-.11m'\z\(hy\v'.11m'\h'|\\n:u'
.ds th \*(#[\v'.3m'\s+1I\s-1\v'-.3m'\h'-(\w'I'u*2/3)'\s-1o\s+1\*(#]
.ds Th \*(#[\s+2I\s-2\h'-\w'I'u*3/5'\v'-.3m'o\v'.3m'\*(#]
.ds ae a\h'-(\w'a'u*4/10)'e
.ds Ae A\h'-(\w'A'u*4/10)'E
. \" corrections for vroff
.if v .ds ~ \\k:\h'-(\\n(.wu*9/10-\*(#H)'\s-2\u~\d\s+2\h'|\\n:u'
.if v .ds ^ \\k:\h'-(\\n(.wu*10/11-\*(#H)'\v'-.4m'^\v'.4m'\h'|\\n:u'
. \" for low resolution devices (crt and lpr)
.if \n(.H>23 .if \n(.V>19 \
\{\
. ds : e
. ds 8 ss
. ds o a
. ds d- d\h'-1'\(ga
. ds D- D\h'-1'\(hy
. ds th \o'bp'
. ds Th \o'LP'
. ds ae ae
. ds Ae AE
.\}
.rm #[ #] #H #V #F C
.\" ========================================================================
.\"
.IX Title "Env 3"
.TH Env 3 "2002-11-24" "perl v5.8.0" "Perl Programmers Reference Guide"
.SH "NAME"
Env \- perl module that imports environment variables as scalars or arrays
.SH "SYNOPSIS"
.IX Header "SYNOPSIS"
.Vb 3
\& use Env;
\& use Env qw(PATH HOME TERM);
\& use Env qw($SHELL @LD_LIBRARY_PATH);
.Ve
.SH "DESCRIPTION"
.IX Header "DESCRIPTION"
Perl maintains environment variables in a special hash named \f(CW%ENV\fR. For
when this access method is inconvenient, the Perl module \f(CW\*(C`Env\*(C'\fR allows
environment variables to be treated as scalar or array variables.
.PP
The \f(CW\*(C`Env::import()\*(C'\fR function ties environment variables with suitable
names to global Perl variables with the same names. By default it
ties all existing environment variables (\f(CW\*(C`keys %ENV\*(C'\fR) to scalars. If
the \f(CW\*(C`import\*(C'\fR function receives arguments, it takes them to be a list of
variables to tie; it's okay if they don't yet exist. The scalar type
prefix '$' is inferred for any element of this list not prefixed by '$'
or '@'. Arrays are implemented in terms of \f(CW\*(C`split\*(C'\fR and \f(CW\*(C`join\*(C'\fR, using
\&\f(CW$Config::Config{path_sep}\fR as the delimiter.
.PP
After an environment variable is tied, merely use it like a normal variable.
You may access its value
.PP
.Vb 2
\& @path = split(/:/, $PATH);
\& print join("\en", @LD_LIBRARY_PATH), "\en";
.Ve
.PP
or modify it
.PP
.Vb 2
\& $PATH .= ":.";
\& push @LD_LIBRARY_PATH, $dir;
.Ve
.PP
however you'd like. Bear in mind, however, that each access to a tied array
variable requires splitting the environment variable's string anew.
.PP
The code:
.PP
.Vb 2
\& use Env qw(@PATH);
\& push @PATH, '.';
.Ve
.PP
is equivalent to:
.PP
.Vb 2
\& use Env qw(PATH);
\& $PATH .= ":.";
.Ve
.PP
except that if \f(CW$ENV{PATH}\fR started out empty, the second approach leaves
it with the (odd) value "\f(CW\*(C`:.\*(C'\fR\*(L", but the first approach leaves it with \*(R"\f(CW\*(C`.\*(C'\fR".
.PP
To remove a tied environment variable from
the environment, assign it the undefined value
.PP
.Vb 2
\& undef $PATH;
\& undef @LD_LIBRARY_PATH;
.Ve
.SH "LIMITATIONS"
.IX Header "LIMITATIONS"
On \s-1VMS\s0 systems, arrays tied to environment variables are read\-only. Attempting
to change anything will cause a warning.
.SH "AUTHOR"
.IX Header "AUTHOR"
Chip Salzenberg <\fIchip@fin.uucp\fR>
and
Gregor N. Purdy <\fIgregor@focusresearch.com\fR>
|