1# Socket Error Codes
2
3> **NOTE**
4>
5> This topic describes only module-specific error codes. For details about universal error codes, see [Universal Error Codes](../errorcode-universal.md).
6
7## 2301001 Operation Not Allowed
8
9**Error Message**
10
11Operation not permitted.
12
13**Description**
14
15This error code is reported if an operation is not allowed.
16
17**Cause**
18
19The operation is illegal.
20
21**Procedure**
22
23Check the operation procedure.
24
25## 2301002 File Not Exist
26
27**Error Message**
28
29No such file or directory.
30
31**Description**
32
33This error code is reported if the requested file does not exist.
34
35**Cause**
36
37The requested file does not exist.
38
39**Procedure**
40
41Check the file name or file path.
42
43## 2301003 Process Not Exist
44
45**Error Message**
46
47No such process.
48
49**Description**
50
51This error code is reported if a process does not exist.
52
53**Cause**
54
55The process does not exist.
56
57**Procedure**
58
59Check the process information.
60
61## 2301004 System Call Interrupted
62
63**Error Message**
64
65Interrupted system call.
66
67**Description**
68
69This error code is reported if the system call is interrupted.
70
71**Cause**
72
73The system call is interrupted.
74
75**Procedure**
76
77Rectify system call errors.
78
79**Description of TCP/UDP error codes:**
80> Mapping format of other TCP/UDP Socket error codes: 2301000 + Linux kernel error code (errno). For details, see Linux kernel error codes.
81
82## 2300002 System Internal Error
83
84**Error Message**
85
86System internal error.
87
88**Description**
89
90This error code is reported if a system internal error occurs.
91
92**Cause**
93
941. The memory is abnormal.
95
962. A null pointer is present.
97
98**Procedure**
99
1001. Check whether the memory space is sufficient. If not, clear the memory and try again.
101
1022. Check whether the system is normal. If not, try again later or restart the device.
103
104## 2303104 System Call Interrupted
105
106**Error Message**
107
108Interrupted system call.
109
110**Description**
111
112This error code is reported if the system call is interrupted.
113
114**Cause**
115
116Calling the **connect** function may result in a long blocking time. In such a case, the system generates an interrupt signal and returns an **EINTR** error.
117
118**Procedure**
119
120Call the **connect** function to try network connection again.
121
122## 2303109 Error File Number
123
124**Error Message**
125
126Bad file number.
127
128**Description**
129
130This error code is reported if an operation is performed on a locally closed socket.
131
132**Cause**
133
134The socket FD may be closed.
135
136**Procedure**
137
138Check whether the socket is closed unexpectedly.
139
140## 2303111 Requested Resource Temporarily Unavailable
141
142**Error Message**
143
144Resource temporarily unavailable. Try again.
145
146**Description**
147
148This error code is reported if the requested system resource is temporarily unavailable.
149
150**Cause**
151
152The system resources are in use.
153
154**Procedure**
155
156Try again later.
157
158## 2303188 Socket Operations on Non-Sockets
159
160**Error Message**
161
162Not a socket.
163
164**Description**
165
166This error code is reported if a socket descriptor is not specified for the **socket** parameter.
167
168**Cause**
169
170A socket descriptor is not specified for the **socket** parameter.
171
172**Procedure**
173
174Check whether the descriptor is correctly obtained.
175
176## 2303191 Incorrect Socket Protocol Type
177
178**Error Message**
179
180Incorrect socket protocol type.
181
182**Description**
183
184This error code is reported if the type of the specified socket protocol is incorrect.
185
186**Cause**
187
188The **socket** function is called with an unsupported socket protocol type.
189For example, the protocol type cannot be set to **SOCK_STREAM socket** for the the Internet UDP protocol.
190
191**Procedure**
192
193Check whether the socket protocol type is correct.
194
195## 2303198 Network Address Already In Use
196
197**Error Message**
198
199Address already in use.
200
201**Description**
202
203This error code is reported if a network address has been used.
204
205**Cause**
206
207The probable cause can be any of the following: The application attempts to bind a socket to an IP address/port that has been used for an existing socket. The socket is not properly closed. The socket is still being closed.
208
209**Procedure**
210
211Try another network address.
212
213## 2303199 Failed to Assign the Requested Address
214
215**Error Message**
216
217Address not available.
218
219**Description**
220
221This error code is reported if the requested address is invalid in its context.
222
223**Cause**
224
225The remote address or port is invalid for the remote server.
226
227**Procedure**
228
229Check whether the address or port is correct.
230
231## 2303200 Network Disabled
232
233**Error Message**
234
235Network is down.
236
237**Description**
238
239The network is disabled.
240
241**Cause**
242
243The network service is not started or has been stopped.
244
245**Procedure**
246
247Check the network connection.
248
249## 2303210 Connection Timeout
250
251**Error Message**
252
253Connection timed out.
254
255**Description**
256
257This error code is reported if the connection to the remote server cannot be set up for a long time.
258
259**Cause**
260
261It is probable that a server breakdown has occurred.
262
263**Procedure**
264
265Contact the peer end to rectify the fault.
266
267## 2303501 Null SSL
268
269**Error Message**
270
271SSL is null.
272
273**Description**
274
275This error code is reported if the SSL is null.
276
277**Cause**
278
279The returned error information is null when an internal function fails to be executed.
280
281**Procedure**
282
283Call the function again.
284
285## 2303502 TLS Reading Error
286
287**Error Message**
288
289An error occurred when reading data on the TLS socket.
290
291**Description**
292
293This error code is reported if an error occurs while reading data on the TLS socket.
294
295**Cause**
296
297The underlying socket is blocked.
298
299**Procedure**
300
301Perform data receiving again.
302
303## 2303503 TLS Writing Error
304
305**Error Message**
306
307An error occurred when writing data on the TLS socket.
308
309**Description**
310
311This error code is reported if an error occurs while writing data on the TLS socket.
312
313**Cause**
314
315When the send buffer is full, the underlying socket sends an **EWOUDLBLOCK** error, which means that the server does not read the data sent from the client.
316
317**Procedure**
318
319Rectify the fault on the server side.
320
321## 2303504 x509 Failed to Look Up the x509 Certificate
322
323**Error Message**
324
325An error occurred when verifying the X.509 certificate.
326
327**Description**
328
329An error occurred when verifying the x509 certificate.
330
331**Cause**
332
333The local certificate does not match the server certificate.
334
335**Procedure**
336
337Check whether the local CA matches the server certificate.
338
339## 2303505 TLS System Call Error
340
341**Error Message**
342
343An error occurred in the TLS system call.
344
345**Description**
346
347This error code is reported if the TLS system call fails because of fatal I/O errors.
348
349**Cause**
350
351Network communication fails because of network faults.
352
353**Procedure**
354
355For details, see the Linux kernel error codes (errno).
356
357## 2303506 Failed to Close TLS Connections
358
359**Error Message**
360
361Failed to close the TLS connection.
362
363**Description**
364
365This error code is reported if the TLS/SSL connection to be closed has been disabled.
366
367**Cause**
368
369The TLS/SSL connection to be closed has been disabled.
370
371**Procedure**
372
373Initiate a new TLS/SSL connection.
374