b::concise.3

视频监控网络部分的协议ddns,的模块的实现代码,请大家大胆指正.

.\" Automatically generated by Pod::Man 2.16 (Pod::Simple 3.05)
.\"
.\" 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.  \*(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-
.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\}
.\"
.\" Escape single quotes in literal strings from groff's Unicode transform.
.ie \n(.g .ds Aq \(aq
.el       .ds Aq '
.\"
.\" 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.
.ie \nF \{\
.    de IX
.    tm Index:\\$1\t\\n%\t"\\$2"
..
.    nr % 0
.    rr F
.\}
.el \{\
.    de IX
..
.\}
.\"
.\" 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 "B::Concise 3"
.TH B::Concise 3 "2007-12-18" "perl v5.10.0" "Perl Programmers Reference Guide"
.\" For nroff, turn off justification.  Always turn off hyphenation; it makes
.\" way too many mistakes in technical documents.
.if n .ad l
.nh
.SH "NAME"
B::Concise \- Walk Perl syntax tree, printing concise info about ops
.SH "SYNOPSIS"
.IX Header "SYNOPSIS"
.Vb 1
\&    perl \-MO=Concise[,OPTIONS] foo.pl
\&
\&    use B::Concise qw(set_style add_callback);
.Ve
.SH "DESCRIPTION"
.IX Header "DESCRIPTION"
This compiler backend prints the internal OPs of a Perl program's syntax
tree in one of several space-efficient text formats suitable for debugging
the inner workings of perl or other compiler backends. It can print OPs in
the order they appear in the \s-1OP\s0 tree, in the order they will execute, or
in a text approximation to their tree structure, and the format of the
information displayed is customizable. Its function is similar to that of
perl's \fB\-Dx\fR debugging flag or the \fBB::Terse\fR module, but it is more
sophisticated and flexible.
.SH "EXAMPLE"
.IX Header "EXAMPLE"
Here's two outputs (or 'renderings'), using the \-exec and \-basic
(i.e. default) formatting conventions on the same code snippet.
.PP
.Vb 9
\&    % perl \-MO=Concise,\-exec \-e \*(Aq$a = $b + 42\*(Aq
\&    1  <0> enter
\&    2  <;> nextstate(main 1 \-e:1) v
\&    3  <#> gvsv[*b] s
\&    4  <$> const[IV 42] s
\& *  5  <2> add[t3] sK/2
\&    6  <#> gvsv[*a] s
\&    7  <2> sassign vKS/2
\&    8  <@> leave[1 ref] vKP/REFC
.Ve
.PP
In this \-exec rendering, each opcode is executed in the order shown.
The add opcode, marked with '*', is discussed in more detail.
.PP
The 1st column is the op's sequence number, starting at 1, and is
displayed in base 36 by default.  Here they're purely linear; the
sequences are very helpful when looking at code with loops and
branches.
.PP
The symbol between angle brackets indicates the op's type, for
example; <2> is a \s-1BINOP\s0, <@> a \s-1LISTOP\s0, and <#> is a \s-1PADOP\s0, which is
used in threaded perls. (see \*(L"\s-1OP\s0 class abbreviations\*(R").
.PP
The opname, as in \fB'add[t1]'\fR, may be followed by op-specific
information in parentheses or brackets (ex \fB'[t1]'\fR).
.PP
The op-flags (ex \fB'sK/2'\fR) are described in (\*(L"\s-1OP\s0 flags
abbreviations\*(R").
.PP
.Vb 11
\&    % perl \-MO=Concise \-e \*(Aq$a = $b + 42\*(Aq
\&    8  <@> leave[1 ref] vKP/REFC \->(end)
\&    1     <0> enter \->2
\&    2     <;> nextstate(main 1 \-e:1) v \->3
\&    7     <2> sassign vKS/2 \->8
\& *  5        <2> add[t1] sK/2 \->6
\&    \-           <1> ex\-rv2sv sK/1 \->4
\&    3              <$> gvsv(*b) s \->4
\&    4           <$> const(IV 42) s \->5
\&    \-        <1> ex\-rv2sv sKRM*/1 \->7
\&    6           <$> gvsv(*a) s \->7
.Ve
.PP
The default rendering is top-down, so they're not in execution order.
This form reflects the way the stack is used to parse and evaluate
expressions; the add operates on the two terms below it in the tree.
.PP
Nullops appear as \f(CW\*(C`ex\-opname\*(C'\fR, where \fIopname\fR is an op that has been
optimized away by perl.  They're displayed with a sequence-number of
\&'\-', because they are not executed (they don't appear in previous
example), they're printed here because they reflect the parse.
.PP
The arrow points to the sequence number of the next op; they're not
displayed in \-exec mode, for obvious reasons.
.PP
Note that because this rendering was done on a non-threaded perl, the
PADOPs in the previous examples are now SVOPs, and some (but not all)
of the square brackets have been replaced by round ones.  This is a
subtle feature to provide some visual distinction between renderings
on threaded and un-threaded perls.
.SH "OPTIONS"
.IX Header "OPTIONS"
Arguments that don't start with a hyphen are taken to be the names of
subroutines to render; if no such functions are specified, the main
body of the program (outside any subroutines, and not including use'd
or require'd files) is rendered.  Passing \f(CW\*(C`BEGIN\*(C'\fR, \f(CW\*(C`UNITCHECK\*(C'\fR,
\&\f(CW\*(C`CHECK\*(C'\fR, \f(CW\*(C`INIT\*(C'\fR, or \f(CW\*(C`END\*(C'\fR will cause all of the corresponding
special blocks to be printed.  Arguments must follow options.
.PP
Options affect how things are rendered (ie printed).  They're presented
here by their visual effect, 1st being strongest.  They're grouped
according to how they interrelate; within each group the options are
mutually exclusive (unless otherwise stated).
.Sh "Options for Opcode Ordering"
.IX Subsection "Options for Opcode Ordering"
These options control the 'vertical display' of opcodes.  The display
\&'order' is also called 'mode' elsewhere in this document.
.IP "\fB\-basic\fR" 4
.IX Item "-basic"
Print OPs in the order they appear in the \s-1OP\s0 tree (a preorder
traversal, starting at the root). The indentation of each \s-1OP\s0 shows its
level in the tree, and the '\->' at the end of the line indicates the
next opcode in execution order.  This mode is the default, so the flag
is included simply for completeness.
.IP "\fB\-exec\fR" 4
.IX Item "-exec"
Print OPs in the order they would normally execute (for the majority
of constructs this is a postorder traversal of the tree, ending at the
root). In most cases the \s-1OP\s0 that usually follows a given \s-1OP\s0 will
appear directly below it; alternate paths are shown by indentation. In
cases like loops when control jumps out of a linear path, a 'goto'
line is generated.
.IP "\fB\-tree\fR" 4
.IX Item "-tree"
Print OPs in a text approximation of a tree, with the root of the tree
at the left and 'left\-to\-right' order of children transformed into
\&'top\-to\-bottom'. Because this mode grows both to the right and down,
it isn't suitable for large programs (unless you have a very wide
terminal).
.Sh "Options for Line-Style"
.IX Subsection "Options for Line-Style"
These options select the line-style (or just style) used to render
each opcode, and dictates what info is actually printed into each line.
.IP "\fB\-concise\fR" 4
.IX Item "-concise"
Use the author's favorite set of formatting conventions. This is the
default, of course.
.IP "\fB\-terse\fR" 4
.IX Item "-terse"
Use formatting conventions that emulate the output of \fBB::Terse\fR. The
basic mode is almost indistinguishable from the real \fBB::Terse\fR, and the
exec mode looks very similar, but is in a more logical order and lacks
curly brackets. \fBB::Terse\fR doesn't have a tree mode, so the tree mode
is only vaguely reminiscent of \fBB::Terse\fR.