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
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
|
<html>
<head><title>
HDF5/H5E Draft API Specification
</title></head>
<body>
<center>
<h1>H5E: Error Interface</h1>
</center>
<h2>Error API Functions</h2>
These functions provide error handling capabilities in the HDF5 environment.
<p>
Provides error handling in the form of a stack. The FUNC_ENTER() macro
clears the error stack whenever an API function is entered. When an error
is detected, an entry is pushed onto the stack. As the functions unwind
additional entries are pushed onto the stack. The API function will return
some indication that an error occurred and the application can print the
error stack.
<p>
Certain API functions in the H5E package (such as H5Eprint())
do not clear the error stack. Otherwise, any function which
doesn't have an underscore immediately after the package name
will clear the error stack. For instance, H5Fopen() clears
the error stack while H5F_open() does not.
<p>
An error stack has a fixed maximum size. If this size is
exceeded then the stack will be truncated and only the
inner-most functions will have entries on the stack. This is
expected to be a rare condition.
<p>
Each thread has its own error stack, but since
multi-threading has not been added to the library yet, this
package maintains a single error stack. The error stack is
statically allocated to reduce the complexity of handling
errors within the H5E package.
<table border=0>
<tr><td valign=top>
<ul>
<li><a href="#Error-SetAuto">H5Eset_auto</a>
<li><a href="#Error-GetAuto">H5Eget_auto</a>
<li><a href="#Error-Clear">H5Eclear</a>
</ul>
</td><td> </td><td valign=top>
<ul>
<li><a href="#Error-Print">H5Eprint</a>
<li><a href="#Error-Walk">H5Ewalk</a>
<li><a href="#Error-WalkCB">H5Ewalk_cb</a>
</ul>
</td><td> </td><td valign=top>
<ul>
<li><a href="#Error-GetMajor">H5Eget_major</a>
<li><a href="#Error-GetMinor">H5Eget_minor</a>
</ul>
</td></tr>
</table>
<hr>
<dl>
<dt><strong>Name:</strong> <a name="Error-SetAuto">H5Eset_auto</a>
<dt><strong>Signature:</strong>
<dd><em>herr_t</em> <code>H5Eset_auto</code>(<em>H5E_auto_t</em> <code>func</code>,
<em>void *</em><code>client_data</code>
)
<dt><strong>Purpose:</strong>
<dd>Turns automatic error printing on or off.
<dt><strong>Description:</strong>
<dd>SC: H5Eset_auto turns on or off automatic printing of errors.
When turned on (non-null <code>func</code> pointer),
any API function which returns an error indication will
first call <code>func</code>, passing it <code>client_data</code>
as an argument.
<p>
The default values before this function is called are
H5Eprint() with client data being the standard error stream,
stderr.
<p>
Automatic stack traversal is always in the H5E_WALK_DOWNWARD
direction.
<p>
UG: If <em>func</em> is not a null pointer, then the function to
which it points will be called automatically when an API
function is about to return an indication of failure. The
function is called with a single argument, the
<em>client_data</em> pointer. When the library is first
initialized the auto printing function is set to
<code>H5Eprint()</code> (cast appropriately) and
<em>client_data</em> is the standard error stream pointer,
<code>stderr</code>.
<p>
<b>UG signature line reads</b>
<br><code>herr_t H5Eset_auto (herr_t(*<em>func</em>)(void*),
void *<em>client_data</em>)</code>.
<br><b>The UG signature line for H5Eget_auto reads similarly.</b>
<p>
<dt><strong>Parameters:</strong>
<dl>
<dt><em>H5E_auto_t</em> <code>func</code>
<dd>Function to be called upon an error condition.
<dt><em>void *</em><code>client_data</code>
<dd>Data passed to the error function.
</dl>
<dt><strong>Returns:</strong>
<dd>Returns SUCCEED (0) if successful;
otherwise FAIL (-1).
</dl>
<hr>
<dl>
<dt><strong>Name:</strong> <a name="Error-GetAuto">H5Eget_auto</a>
<dt><strong>Signature:</strong>
<dd><em>herr_t</em> <code>H5Eget_auto</code>(<em>H5E_auto_t *</em> <code>func</code>,
<em>void **</em><code>client_data</code>
)
<dt><strong>Purpose:</strong>
<dd>Returns the current settings for the automatic error stack
traversal function and its data.
<dt><strong>Description:</strong>
<dd>SC: H5Eget_auto returns the current settings for the automatic error stack
traversal function and its data. Either (or both) arguments
may be null in which case the value is not returned.
<p>
UG: This function returns the current automatic error traversal
settings through the <em>func</em> and <em>client_data</em>
arguments. Either (or both) arguments may be null pointers in
which case the corresponding information is not returned.
<dt><strong>Parameters:</strong>
<dl>
<dt><em>H5E_auto_t *</em> <code>func</code>
<dd>Current setting for the function to be called upon an
error condition.
<dt><em>void **</em><code>client_data</code>
<dd>Current setting for the data passed to the error function.
</dl>
<dt><strong>Returns:</strong>
<dd>Returns SUCCEED (0) if successful;
otherwise FAIL (-1).
</dl>
<hr>
<dl>
<dt><strong>Name:</strong> <a name="Error-Clear">H5Eclear</a>
<dt><strong>Signature:</strong>
<dd><em>herr_t</em> <code>H5Eclear</code>(<code>void</code>)
<dt><strong>Purpose:</strong>
<dd>Clears the error stack for the current thread.
<dt><strong>Description:</strong>
<dd>SC: H5Eclear clears the error stack for the current thread.
<p>
This function can fail if there are problems initializing the library.
<p>
UG: The error stack can be explicitly cleared by calling this
function. The stack is also cleared whenever an API function
is called, with certain exceptions (for instance,
<code>H5Eprint()</code>).
<dt><strong>Parameters:</strong>
<dl>
<dt><em>paramtype</em> <code>param</code>
<dd>xxx
<dt><i>Should this say "None"?</i>
</dl>
<dt><strong>Returns:</strong>
<dd>Returns SUCCEED (0) if successful;
otherwise FAIL (-1).
</dl>
<hr>
<dl>
<dt><strong>Name:</strong> <a name="Error-Print">H5Eprint</a>
<dt><strong>Signature:</strong>
<dd><em>herr_t</em> <code>H5Eprint</code>(<em>FILE *</em> <code>stream</code>)
<dt><strong>Purpose:</strong>
<dd>Prints the error stack in a default manner.
<dt><strong>Description:</strong>
<dd>SC: H5Eprint prints the error stack in some default way. This is just a
convenience function for H5Ewalk() with a function that
prints error messages. Users are encouraged to write there
own more specific error handlers.
<p>
UG: The error stack is printed on the specified stream. Even if
the error stack is empty a one-line message will be printed:
<code>HDF5-DIAG: Error detected in thread 0.</code>
<dt><strong>Parameters:</strong>
<dl>
<dt><em>FILE *</em> <code>stream</code>
<dd>xxx
</dl>
<dt><strong>Returns:</strong>
<dd>Returns SUCCEED (0) if successful;
otherwise FAIL (-1).
</dl>
<hr>
<dl>
<dt><strong>Name:</strong> <a name="Error-Walk">H5Ewalk</a>
<dt><strong>Signature:</strong>
<dd><em>herr_t</em> <code>H5Ewalk</code>(<em>H5E_direction_t</em> <code>direction</code>,
<em>H5E_walk_t</em> <code>func</code>,
<em>void *</em> <code>client_data</code>
)
<dt><strong>Purpose:</strong>
<dd>Walks the error stack for the current thread, calling a specified
function.
<dt><strong>Description:</strong>
<dd>SC: <code>H5Ewalk</code> walks the error stack for the current thread
and calls the specified function for each error along the way.
<p>
<code>direction</code> determines whether the stack is walked
from the inside out or the outside in.
A value of <code>H5E_WALK_UPWARD</code> means begin with the
most specific error and end at the API;
a value of <code>H5E_WALK_DOWNWARD</code> means to start at the
API and end at the inner-most function where the error was first
detected.
<p>
<code>func</code> will be called for each error in the error stack.
It's arguments will include an index number (beginning at zero
regardless of stack traversal direction), an error stack entry,
and the <code>client_data</code> pointer passed to
<code>H5E_print</code>.
<p>
<code>H5Ewalk</code> can fail if there are problems initializing the library.
<p>
UG: The error stack is traversed and <em>func</em> is called for
each member of the stack. Its arguments are an integer
sequence number beginning at zero (regardless of
<em>direction</em>), a pointer to an error description record,
and the <em>client_data</em> pointer. If <em>direction</em>
is <code>H5E_WALK_UPWARD</code> then traversal begins at the
inner-most function that detected the error and concludes with
the API function. The opposite order is
<code>H5E_WALK_DOWNWARD</code>.
<dt><strong>Parameters:</strong>
<dl>
<dt><em>H5E_direction_t</em> <code>direction</code>
<dd>Direction in which the error stack is to be walked.
<dt><em>H5E_walk_t</em> <code>func</code>
<dd>Function to be called for each error encountered.
<dt><em>void *</em> <code>client_data</code>
<dd>Data to be passed with <code>func</code>.
</dl>
<dt><strong>Returns:</strong>
<dd>Returns SUCCEED (0) if successful;
otherwise FAIL (-1).
</dl>
<hr>
<dl>
<dt><strong>Name:</strong> <a name="Error-WalkCB">H5Ewalk_cb</a>
<dt><strong>Signature:</strong>
<dd><em>herr_t</em> <code>H5Ewalk_cb</code>(<em>int</em> <code>n</code>,
<em>H5E_error_t *</em><code>err_desc</code>,
<em>void</em> <code>*client_data</code>
)
<dt><strong>Purpose:</strong>
<dd>Default error stack traversal callback function
that prints error messages to the specified output stream.
<dt><strong>Description:</strong>
<dd><code>H5Ewalk_cb</code> is a default error stack traversal callback function
that prints error messages to the specified output stream.
It is not meant to be called directly but rather as an
argument to the H5Ewalk() function. This function is called
also by H5Eprint(). Application writers are encouraged to
use this function as a model for their own error stack
walking functions.
<p>
<code>n</code> is a counter for how many times this function has been
called for this particular traversal of the stack. It always
begins at zero for the first error on the stack (either the
top or bottom error, or even both, depending on the traversal
direction and the size of the stack).
<p>
ERR_DESC is an error description. It contains all the
information about a particular error.
<p>
CLIENT_DATA is the same pointer that was passed as the
CLIENT_DATA argument of H5Ewalk(). It is expected to be a
file pointer (or stderr if null).
<dt><strong>Parameters:</strong>
<dl>
<dt><em>int</em> <code>n</code>
<dd>Number of times this function has been called
for this traversal of the stack.
<dt><em>H5E_error_t *</em><code>err_desc</code>
<dd>Error description.
<dt><em>void</em> <code>*client_data</code>
<dd>A file pointer, or <code>stderr</code> if null.
</dl>
<dt><strong>Returns:</strong>
<dd>Returns SUCCEED (0) if successful;
otherwise FAIL (-1).
</dl>
<hr>
<dl>
<dt><strong>Name:</strong> <a name="Error-GetMajor">H5Eget_major</a>
<dt><strong>Signature:</strong>
<dd><em>const char *</em> <code>H5Eget_major</code>(<em>H5E_major_t</em> <code>n</code>)
<dt><strong>Purpose:</strong>
<dd>Returns a character string describing a major error.
<dt><strong>Description:</strong>
<dd>Given a major error number, H5Eget_major returns a constant character string
that describes the error.
<dt><strong>Parameters:</strong>
<dl>
<dt><em>H5E_major_t</em> <code>n</code>
<dd>Major error number.
</dl>
<dt><strong>Returns:</strong>
<dd> Returns a pointer to a character string if successful.
Otherwise returns a pointer to "Invalid major error number".
<br>
<i> ...or how about... </i>
<br>
Returns a pointer to a character string describing the error if successful.
Otherwise returns a pointer to "Invalid major error number".
<br>
<i> ...or ... </i>
<br>
Returns a character string describing the error if successful.
Otherwise returns "Invalid major error number."
</dl>
<hr>
<dl>
<dt><strong>Name:</strong> <a name="Error-GetMinor">H5Eget_minor</a>
<dt><strong>Signature:</strong>
<dd><em>const char *</em> <code>H5Eget_minor</code>(<em>H5E_minor_t</em> <code>n</code>)
<dt><strong>Purpose:</strong>
<dd>Returns a character string describing a minor error.
<dt><strong>Description:</strong>
<dd>Given a minor error number, H5Eget_minor returns a constant character string
that describes the error.
<dt><strong>Parameters:</strong>
<dl>
<dt><em>H5E_minor_t</em> <code>n</code>
<dd>Minor error number.
</dl>
<dt><strong>Returns:</strong>
<dd> Returns a pointer to a character string if successful.
Otherwise returns a pointer to "Invalid minor error number".
<br>
<i> ...or how about... </i>
<br>
Returns a pointer to a character string describing the error if successful.
Otherwise returns a pointer to "Invalid minor error number".
<br>
<i> ...or ... </i>
<br>
Returns a character string describing the error if successful.
Otherwise returns "Invalid minor error number."
</dl>
<hr>
<address>
<a href="mailto:fbaker@ncsa.uiuc.edu">Frank Baker</a>
<br>
<a href="mailto:h5docs@ncsa.uiuc.edu">HDF5 Documentation</a>
<br>
Last modified: 6 July 1998
</body>
</html>
|
