1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
|
.\" Automatically generated by Pod::Man 2.22 (Pod::Simple 3.13)
.\"
.\" Standard preamble:
.\" ========================================================================
.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 (.SS), 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 "xpaget 3"
.TH xpaget 3 "July 23, 2013" "version 2.1.15" "SAORD Documentation"
.\" 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"
\&\fBXPAGet: retrieve data from one or more \s-1XPA\s0 servers\fR
.SH "SYNOPSIS"
.IX Header "SYNOPSIS"
.Vb 1
\& #include <xpa.h>
\&
\& int XPAGet(XPA xpa,
\& char *template, char *paramlist, char *mode,
\& char **bufs, size_t *lens, char **names, char **messages,
\& int n);
.Ve
.SH "DESCRIPTION"
.IX Header "DESCRIPTION"
Retrieve data from one or more \s-1XPA\s0 servers whose class:name identifier
matches the specified template.
.PP
A
template
of the form \*(L"class1:name1\*(R" is sent to the
\&\s-1XPA\s0 name server, which returns a list of at most n matching \s-1XPA\s0
servers. A connection is established with each of these servers and
the paramlist string is passed to the server as the data transfer
request is initiated. If an \s-1XPA\s0 struct is passed to the call, then the
persistent connections are updated as described above. Otherwise,
temporary connections are made to the servers (which will be closed
when the call completes).
.PP
The \fIXPAGet()\fR routine then retrieves data from at most n \s-1XPA\s0 servers,
places these data into n allocated buffers and places the buffer
pointers in the bufs array. The length of each buffer is stored in the
lens array. A string containing the class:name and ip:port is stored
in the name array. If a given server returned an error or the server
callback sends a message back to the client, then the message will be
stored in the associated element of the messages array. \s-1NB:\s0 if
specified, the name and messages arrays must be of size n or greater.
.PP
The returned message string will be of the form:
.PP
.Vb 1
\& XPA$ERROR error\-message (class:name ip:port)
.Ve
.PP
or
.PP
.Vb 1
\& XPA$MESSAGE message (class:name ip:port)
.Ve
.PP
Note that when there is an error stored in an messages entry, the
corresponding bufs and lens entry may or may not be \s-1NULL\s0 and 0
(respectively), depending on the particularities of the server.
.PP
The return value will contain the actual number of servers that were
processed. This value thus will hold the number of valid entries in
the bufs, lens, names, and messages arrays, and can be used to loop
through these arrays. In names and/or messages is \s-1NULL\s0, no information is
passed back in that array.
.PP
The bufs, names, and messages arrays should be freed upon completion (if
they are not \s-1NULL\s0);
.PP
The mode string is of the form: \*(L"key1=value1,key2=value2,...\*(R"
The following keywords are recognized:
.PP
.Vb 4
\& key value default explanation
\& \-\-\-\-\-\- \-\-\-\-\-\-\-\- \-\-\-\-\-\-\-\- \-\-\-\-\-\-\-\-\-\-\-
\& ack true/false true if false, don\*(Aqt wait for ack from server (after callback completes)
\& doxpa true/false true client processes xpa requests
.Ve
.PP
The ack keyword is not very useful, since the server completes the callback
in order to return the data anyway. It is here for completion (and perhaps
for future usefulness).
.PP
Normally, an \s-1XPA\s0 client will process incoming \s-1XPA\s0 server requests
while awaiting the completion of the client request. Setting this
variable to \*(L"false\*(R" will prevent \s-1XPA\s0 server requests from being
processed by the client.
.PP
\&\fBExample:\fR
.PP
.Vb 1
\& #include <xpa.h>
\&
\& #define NXPA 10
\& int i, got;
\& size_t lens[NXPA];
\& char *bufs[NXPA];
\& char *names[NXPA];
\& char *messages[NXPA];
\& got = XPAGet(NULL, "ds9", "file", NULL, bufs, lens, names, messages,
\& NXPA);
\& for(i=0; i<got; i++){
\& if( messages[i] == NULL ){
\& /* process buf contents */
\& ProcessImage(bufs[i], ...);
\& free(bufs[i]);
\& }
\& else{
\& /* error processing */
\& fprintf(stderr, "ERROR: %s (%s)\en", messages[i], names[i]);
\& }
\& if( names[i] )
\& free(names[i]);
\& if( messages[i] )
\& free(messages[i]);
\& }
.Ve
.SH "SEE ALSO"
.IX Header "SEE ALSO"
See xpa(n) for a list of \s-1XPA\s0 help pages
|
