1explain_tcflush(3) Library Functions Manual explain_tcflush(3)
2
6 explain_tcflush - explain tcflush(3) errors
7
9 #include <libexplain/tcflush.h>
10 const char *explain_tcflush(int fildes, int selector);
11 const char *explain_errno_tcflush(int errnum, int fildes, int selec‐
12 tor);
13 void explain_message_tcflush(char *message, int message_size, int
14 fildes, int selector);
15 void explain_message_errno_tcflush(char *message, int message_size, int
16 errnum, int fildes, int selector);
17
19 These functions may be used to obtain explanations for errors returned
20 by the tcflush(3) system call.
21 explain_tcflush
23 const char *explain_tcflush(int fildes, int selector);
24 The explain_tcflush function is used to obtain an explanation of an
26 error returned by the tcflush(3) system call. The least the message
27 will contain is the value of strerror(errno), but usually it will do
28 much better, and indicate the underlying cause in more detail.
29 The errno global variable will be used to obtain the error value to be
31 decoded.
32 fildes The original fildes, exactly as passed to the tcflush(3) system
34 call.
35 selector
37 The original selector, exactly as passed to the tcflush(3) sys‐
38 tem call.
39 Returns:
41 The message explaining the error. This message buffer is shared
42 by all libexplain functions which do not supply a buffer in
43 their argument list. This will be overwritten by the next call
44 to any libexplain function which shares this buffer, including
45 other threads.
46 Note: This function is not thread safe, because it shares a return buf‐
48 fer across all threads, and many other functions in this library.
49 Example: This function is intended to be used in a fashion similar to
51 the following example:
52 if (tcflush(fildes, selector) < 0)
53 {
54 fprintf(stderr, "%s\n", explain_tcflush(fildes, selector));
55 exit(EXIT_FAILURE);
56 }
57 The above code example is available pre‐packaged as the
59 explain_tcflush_or_die(3) function.
60 explain_errno_tcflush
62 const char *explain_errno_tcflush(int errnum, int fildes, int selec‐
63 tor);
64 The explain_errno_tcflush function is used to obtain an explanation of
66 an error returned by the tcflush(3) system call. The least the message
67 will contain is the value of strerror(errno), but usually it will do
68 much better, and indicate the underlying cause in more detail.
69 errnum The error value to be decoded, usually obtained from the errno
71 global variable just before this function is called. This is
72 necessary if you need to call any code between the system call
73 to be explained and this function, because many libc functions
74 will alter the value of errno.
75 fildes The original fildes, exactly as passed to the tcflush(3) system
77 call.
78 selector
80 The original selector, exactly as passed to the tcflush(3) sys‐
81 tem call.
82 Returns:
84 The message explaining the error. This message buffer is shared
85 by all libexplain functions which do not supply a buffer in
86 their argument list. This will be overwritten by the next call
87 to any libexplain function which shares this buffer, including
88 other threads.
89 Note: This function is not thread safe, because it shares a return buf‐
91 fer across all threads, and many other functions in this library.
92 Example: This function is intended to be used in a fashion similar to
94 the following example:
95 if (tcflush(fildes, selector) < 0)
96 {
97 int err = errno;
98 fprintf(stderr, "%s\n", explain_errno_tcflush(err, fildes,
99 selector));
100 exit(EXIT_FAILURE);
101 }
102 The above code example is available pre‐packaged as the
104 explain_tcflush_or_die(3) function.
105 explain_message_tcflush
107 void explain_message_tcflush(char *message, int message_size, int
108 fildes, int selector);
109 The explain_message_tcflush function is used to obtain an explanation
111 of an error returned by the tcflush(3) system call. The least the mes‐
112 sage will contain is the value of strerror(errno), but usually it will
113 do much better, and indicate the underlying cause in more detail.
114 The errno global variable will be used to obtain the error value to be
116 decoded.
117 message The location in which to store the returned message. If a suit‐
119 able message return buffer is supplied, this function is thread
120 safe.
121 message_size
123 The size in bytes of the location in which to store the
124 returned message.
125 fildes The original fildes, exactly as passed to the tcflush(3) system
127 call.
128 selector
130 The original selector, exactly as passed to the tcflush(3) sys‐
131 tem call.
132 Example: This function is intended to be used in a fashion similar to
134 the following example:
135 if (tcflush(fildes, selector) < 0)
136 {
137 char message[3000];
138 explain_message_tcflush(message, sizeof(message), fildes,
139 selector);
140 fprintf(stderr, "%s\n", message);
141 exit(EXIT_FAILURE);
142 }
143 The above code example is available pre‐packaged as the
145 explain_tcflush_or_die(3) function.
146 explain_message_errno_tcflush
148 void explain_message_errno_tcflush(char *message, int message_size, int
149 errnum, int fildes, int selector);
150 The explain_message_errno_tcflush function is used to obtain an expla‐
152 nation of an error returned by the tcflush(3) system call. The least
153 the message will contain is the value of strerror(errno), but usually
154 it will do much better, and indicate the underlying cause in more
155 detail.
156 message The location in which to store the returned message. If a suit‐
158 able message return buffer is supplied, this function is thread
159 safe.
160 message_size
162 The size in bytes of the location in which to store the
163 returned message.
164 errnum The error value to be decoded, usually obtained from the errno
166 global variable just before this function is called. This is
167 necessary if you need to call any code between the system call
168 to be explained and this function, because many libc functions
169 will alter the value of errno.
170 fildes The original fildes, exactly as passed to the tcflush(3) system
172 call.
173 selector
175 The original selector, exactly as passed to the tcflush(3) sys‐
176 tem call.
177 Example: This function is intended to be used in a fashion similar to
179 the following example:
180 if (tcflush(fildes, selector) < 0)
181 {
182 int err = errno;
183 char message[3000];
184 explain_message_errno_tcflush(message, sizeof(message), err,
185 fildes, selector);
186 fprintf(stderr, "%s\n", message);
187 exit(EXIT_FAILURE);
188 }
189 The above code example is available pre‐packaged as the
191 explain_tcflush_or_die(3) function.
192
194 tcflush(3)
195 discard terminal data
196 explain_tcflush_or_die(3)
198 discard terminal data and report errors
199
201 libexplain version 1.4
202 Copyright (C) 2009 Peter Miller
203 explain_tcflush(3)