1explain_tcsendbreak(3) Library Functions Manual explain_tcsendbreak(3)
2
6 explain_tcsendbreak - explain tcsendbreak(3) errors
7
9 #include <libexplain/tcsendbreak.h>
10 const char *explain_tcsendbreak(int fildes, int duration);
11 const char *explain_errno_tcsendbreak(int errnum, int fildes, int dura‐
12 tion);
13 void explain_message_tcsendbreak(char *message, int message_size, int
14 fildes, int duration);
15 void explain_message_errno_tcsendbreak(char *message, int message_size,
16 int errnum, int fildes, int duration);
17
19 These functions may be used to obtain explanations for errors returned
20 by the tcsendbreak(3) system call.
21 explain_tcsendbreak
23 const char *explain_tcsendbreak(int fildes, int duration);
24 The explain_tcsendbreak function is used to obtain an explanation of an
26 error returned by the tcsendbreak(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 tcsendbreak(3)
34 system call.
35 duration
37 The original duration, exactly as passed to the tcsendbreak(3)
38 system 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 (tcsendbreak(fildes, duration) < 0)
53 {
54 fprintf(stderr, "%s\n", explain_tcsendbreak(fildes, dura‐
55 tion));
56 exit(EXIT_FAILURE);
57 }
58 The above code example is available pre‐packaged as the explain_tcsend‐
60 break_or_die(3) function.
61 explain_errno_tcsendbreak
63 const char *explain_errno_tcsendbreak(int errnum, int fildes, int dura‐
64 tion);
65 The explain_errno_tcsendbreak function is used to obtain an explanation
67 of an error returned by the tcsendbreak(3) system call. The least the
68 message will contain is the value of strerror(errno), but usually it
69 will do much better, and indicate the underlying cause in more detail.
70 errnum The error value to be decoded, usually obtained from the errno
72 global variable just before this function is called. This is
73 necessary if you need to call any code between the system call
74 to be explained and this function, because many libc functions
75 will alter the value of errno.
76 fildes The original fildes, exactly as passed to the tcsendbreak(3)
78 system call.
79 duration
81 The original duration, exactly as passed to the tcsendbreak(3)
82 system call.
83 Returns:
85 The message explaining the error. This message buffer is shared
86 by all libexplain functions which do not supply a buffer in
87 their argument list. This will be overwritten by the next call
88 to any libexplain function which shares this buffer, including
89 other threads.
90 Note: This function is not thread safe, because it shares a return buf‐
92 fer across all threads, and many other functions in this library.
93 Example: This function is intended to be used in a fashion similar to
95 the following example:
96 if (tcsendbreak(fildes, duration) < 0)
97 {
98 int err = errno;
99 fprintf(stderr, "%s\n", explain_errno_tcsendbreak(err,
100 fildes, duration));
101 exit(EXIT_FAILURE);
102 }
103 The above code example is available pre‐packaged as the explain_tcsend‐
105 break_or_die(3) function.
106 explain_message_tcsendbreak
108 void explain_message_tcsendbreak(char *message, int message_size, int
109 fildes, int duration);
110 The explain_message_tcsendbreak function is used to obtain an explana‐
112 tion of an error returned by the tcsendbreak(3) system call. The least
113 the message will contain is the value of strerror(errno), but usually
114 it will do much better, and indicate the underlying cause in more
115 detail.
116 The errno global variable will be used to obtain the error value to be
118 decoded.
119 message The location in which to store the returned message. If a suit‐
121 able message return buffer is supplied, this function is thread
122 safe.
123 message_size
125 The size in bytes of the location in which to store the
126 returned message.
127 fildes The original fildes, exactly as passed to the tcsendbreak(3)
129 system call.
130 duration
132 The original duration, exactly as passed to the tcsendbreak(3)
133 system call.
134 Example: This function is intended to be used in a fashion similar to
136 the following example:
137 if (tcsendbreak(fildes, duration) < 0)
138 {
139 char message[3000];
140 explain_message_tcsendbreak(message, sizeof(message),
141 fildes, duration);
142 fprintf(stderr, "%s\n", message);
143 exit(EXIT_FAILURE);
144 }
145 The above code example is available pre‐packaged as the explain_tcsend‐
147 break_or_die(3) function.
148 explain_message_errno_tcsendbreak
150 void explain_message_errno_tcsendbreak(char *message, int message_size,
151 int errnum, int fildes, int duration);
152 The explain_message_errno_tcsendbreak function is used to obtain an
154 explanation of an error returned by the tcsendbreak(3) system call.
155 The least the message will contain is the value of strerror(errno), but
156 usually it will do much better, and indicate the underlying cause in
157 more detail.
158 message The location in which to store the returned message. If a suit‐
160 able message return buffer is supplied, this function is thread
161 safe.
162 message_size
164 The size in bytes of the location in which to store the
165 returned message.
166 errnum The error value to be decoded, usually obtained from the errno
168 global variable just before this function is called. This is
169 necessary if you need to call any code between the system call
170 to be explained and this function, because many libc functions
171 will alter the value of errno.
172 fildes The original fildes, exactly as passed to the tcsendbreak(3)
174 system call.
175 duration
177 The original duration, exactly as passed to the tcsendbreak(3)
178 system call.
179 Example: This function is intended to be used in a fashion similar to
181 the following example:
182 if (tcsendbreak(fildes, duration) < 0)
183 {
184 int err = errno;
185 char message[3000];
186 explain_message_errno_tcsendbreak(message, sizeof(message),
187 err, fildes, duration);
188 fprintf(stderr, "%s\n", message);
189 exit(EXIT_FAILURE);
190 }
191 The above code example is available pre‐packaged as the explain_tcsend‐
193 break_or_die(3) function.
194
196 tcsendbreak(3)
197 send terminal line break
198 explain_tcsendbreak_or_die(3)
200 send terminal line break and report errors
201
203 libexplain version 1.4
204 Copyright (C) 2009 Peter Miller
205 explain_tcsendbreak(3)