-
Notifications
You must be signed in to change notification settings - Fork 0
/
Copy pathfeatures.connection-handling.html
273 lines (273 loc) · 5.8 KB
/
features.connection-handling.html
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
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
<HTML
><HEAD
><TITLE
>Connection handling</TITLE
><META
NAME="GENERATOR"
CONTENT="Modular DocBook HTML Stylesheet Version 1.57"><LINK
REL="HOME"
TITLE="PHP Manual"
HREF="manual.html"><LINK
REL="UP"
TITLE="Features"
HREF="features.html"><LINK
REL="PREVIOUS"
TITLE="Using remote files"
HREF="features.remote-files.html"><LINK
REL="NEXT"
TITLE="Persistent Database Connections"
HREF="features.persistent-connections.html"><META
NAME="HTTP_EQUIV"
CONTENT="text/html; charset=ISO-8859-1"></HEAD
><BODY
CLASS="chapter"
BGCOLOR="#FFFFFF"
TEXT="#000000"
LINK="#0000FF"
VLINK="#840084"
ALINK="#0000FF"
><DIV
CLASS="NAVHEADER"
><TABLE
WIDTH="100%"
BORDER="0"
CELLPADDING="0"
CELLSPACING="0"
><TR
><TH
COLSPAN="3"
ALIGN="center"
>PHP Manual</TH
></TR
><TR
><TD
WIDTH="10%"
ALIGN="left"
VALIGN="bottom"
><A
HREF="features.remote-files.html"
>Prev</A
></TD
><TD
WIDTH="80%"
ALIGN="center"
VALIGN="bottom"
></TD
><TD
WIDTH="10%"
ALIGN="right"
VALIGN="bottom"
><A
HREF="features.persistent-connections.html"
>Next</A
></TD
></TR
></TABLE
><HR
ALIGN="LEFT"
WIDTH="100%"></DIV
><DIV
CLASS="chapter"
><H1
><A
NAME="features.connection-handling"
>Chapter 21. Connection handling</A
></H1
><DIV
CLASS="note"
><BLOCKQUOTE
CLASS="note"
><P
><B
>Note: </B
>The following applies to 3.0.7 and later.</P
></BLOCKQUOTE
></DIV
><P
> Internally in PHP a connection status is maintained. There are 3
possible states:
<P
></P
><UL
><LI
><P
>0 - NORMAL</P
></LI
><LI
><P
>1 - ABORTED</P
></LI
><LI
><P
>2 - TIMEOUT</P
></LI
></UL
>
</P
><P
> When a PHP script is running normally the NORMAL state, is active.
If the remote client disconnects the ABORTED state flag is
turned on. A remote client disconnect is usually caused by the
user hitting his STOP button. If the PHP-imposed time limit (see
<A
HREF="function.set-time-limit.html"
><B
CLASS="function"
>set_time_limit()</B
></A
>) is hit, the TIMEOUT state flag
is turned on.</P
><P
> You can decide whether or not you want a client disconnect to cause
your script to be aborted. Sometimes it is handy to always have your
scripts run to completion even if there is no remote browser receiving
the output. The default behaviour is however for your script to be
aborted when the remote client disconnects. This behaviour can be
set via the ignore_user_abort php3.ini directive as well as through
the corresponding php3_ignore_user_abort Apache .conf directive or
with the <A
HREF="function.ignore-user-abort.html"
><B
CLASS="function"
>ignore_user_abort()</B
></A
> function. If you do
not tell PHP to ignore a user abort and the user aborts, your script
will terminate. The one exception is if you have registered a shutdown
function using <A
HREF="function.register-shutdown-function.html"
><B
CLASS="function"
>register_shutdown_function()</B
></A
>. With a
shutdown function, when the remote user hits his STOP button, the
next time your script tries to output something PHP will detect that
the connection has been aborted and the shutdown function is called.
This shutdown function will also get called at the end of your script
terminating normally, so to do something different in case of a client
diconnect you can use the <A
HREF="function.connection-aborted.html"
><B
CLASS="function"
>connection_aborted()</B
></A
>
function. This function will return true if the connection was
aborted.</P
><P
> Your script can also be terminated by the built-in script timer.
The default timeout is 30 seconds. It can be changed using
the max_execution_time php3.ini directive or the corresponding
php3_max_execution_time Apache .conf directive as well as with
the <A
HREF="function.set-time-limit.html"
><B
CLASS="function"
>set_time_limit()</B
></A
> function. When the timer
expires the script will be aborted and as with the above client
disconnect case, if a shutdown function has been registered it will
be called. Within this shutdown function you can check to see if
a timeout caused the shutdown function to be called by calling the
<A
HREF="function.connection-timeout.html"
><B
CLASS="function"
>connection_timeout()</B
></A
> function. This function will
return true if a timeout caused the shutdown function to be called.</P
><P
> One thing to note is that both the ABORTED and the TIMEOUT states
can be active at the same time. This is possible if you tell
PHP to ignore user aborts. PHP will still note the fact that
a user may have broken the connection, but the script will keep
running. If it then hits the time limit it will be aborted and
your shutdown function, if any, will be called. At this point
you will find that <A
HREF="function.connection-timeout.html"
><B
CLASS="function"
>connection_timeout()</B
></A
>
and <A
HREF="function.connection-aborted.html"
><B
CLASS="function"
>connection_aborted()</B
></A
> return true.
You can also check both states in a single call by using the
<A
HREF="function.connection-status.html"
><B
CLASS="function"
>connection_status()</B
></A
>. This function returns a
bitfield of the active states. So, if both states are active it
would return 3, for example.</P
></DIV
><DIV
CLASS="NAVFOOTER"
><HR
ALIGN="LEFT"
WIDTH="100%"><TABLE
WIDTH="100%"
BORDER="0"
CELLPADDING="0"
CELLSPACING="0"
><TR
><TD
WIDTH="33%"
ALIGN="left"
VALIGN="top"
><A
HREF="features.remote-files.html"
>Prev</A
></TD
><TD
WIDTH="34%"
ALIGN="center"
VALIGN="top"
><A
HREF="manual.html"
>Home</A
></TD
><TD
WIDTH="33%"
ALIGN="right"
VALIGN="top"
><A
HREF="features.persistent-connections.html"
>Next</A
></TD
></TR
><TR
><TD
WIDTH="33%"
ALIGN="left"
VALIGN="top"
>Using remote files</TD
><TD
WIDTH="34%"
ALIGN="center"
VALIGN="top"
><A
HREF="features.html"
>Up</A
></TD
><TD
WIDTH="33%"
ALIGN="right"
VALIGN="top"
>Persistent Database Connections</TD
></TR
></TABLE
></DIV
></BODY
></HTML
>