1explain_stime(3) Library Functions Manual explain_stime(3)
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6 explain_stime - explain stime(2) errors
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9 #include <libexplain/stime.h>
10 const char *explain_stime(time_t *t);
11 const char *explain_errno_stime(int errnum, time_t *t);
12 void explain_message_stime(char *message, int message_size, time_t *t);
13 void explain_message_errno_stime(char *message, int message_size, int
14 errnum, time_t *t);
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17 These functions may be used to obtain explanations for errors returned
18 by the stime(2) system call.
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20 explain_stime
21 const char *explain_stime(time_t *t);
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23 The explain_stime function is used to obtain an explanation of an error
24 returned by the stime(2) system call. The least the message will con‐
25 tain is the value of strerror(errno), but usually it will do much bet‐
26 ter, and indicate the underlying cause in more detail.
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28 The errno global variable will be used to obtain the error value to be
29 decoded.
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31 t The original t, exactly as passed to the stime(2) system call.
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33 Returns:
34 The message explaining the error. This message buffer is shared
35 by all libexplain functions which do not supply a buffer in
36 their argument list. This will be overwritten by the next call
37 to any libexplain function which shares this buffer, including
38 other threads.
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40 Note: This function is not thread safe, because it shares a return buf‐
41 fer across all threads, and many other functions in this library.
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43 Example: This function is intended to be used in a fashion similar to
44 the following example:
45 if (stime(t) < 0)
46 {
47 fprintf(stderr, "%s\n", explain_stime(t));
48 exit(EXIT_FAILURE);
49 }
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51 The above code example is available pre‐packaged as the
52 explain_stime_or_die(3) function.
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54 explain_errno_stime
55 const char *explain_errno_stime(int errnum, time_t *t);
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57 The explain_errno_stime function is used to obtain an explanation of an
58 error returned by the stime(2) system call. The least the message will
59 contain is the value of strerror(errno), but usually it will do much
60 better, and indicate the underlying cause in more detail.
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62 errnum The error value to be decoded, usually obtained from the errno
63 global variable just before this function is called. This is
64 necessary if you need to call any code between the system call
65 to be explained and this function, because many libc functions
66 will alter the value of errno.
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68 t The original t, exactly as passed to the stime(2) system call.
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70 Returns:
71 The message explaining the error. This message buffer is shared
72 by all libexplain functions which do not supply a buffer in
73 their argument list. This will be overwritten by the next call
74 to any libexplain function which shares this buffer, including
75 other threads.
76
77 Note: This function is not thread safe, because it shares a return buf‐
78 fer across all threads, and many other functions in this library.
79
80 Example: This function is intended to be used in a fashion similar to
81 the following example:
82 if (stime(t) < 0)
83 {
84 int err = errno;
85 fprintf(stderr, "%s\n", explain_errno_stime(err, t));
86 exit(EXIT_FAILURE);
87 }
88
89 The above code example is available pre‐packaged as the
90 explain_stime_or_die(3) function.
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92 explain_message_stime
93 void explain_message_stime(char *message, int message_size, time_t *t);
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95 The explain_message_stime function is used to obtain an explanation of
96 an error returned by the stime(2) system call. The least the message
97 will contain is the value of strerror(errno), but usually it will do
98 much better, and indicate the underlying cause in more detail.
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100 The errno global variable will be used to obtain the error value to be
101 decoded.
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103 message The location in which to store the returned message. If a suit‐
104 able message return buffer is supplied, this function is thread
105 safe.
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107 message_size
108 The size in bytes of the location in which to store the
109 returned message.
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111 t The original t, exactly as passed to the stime(2) system call.
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113 Example: This function is intended to be used in a fashion similar to
114 the following example:
115 if (stime(t) < 0)
116 {
117 char message[3000];
118 explain_message_stime(message, sizeof(message), t);
119 fprintf(stderr, "%s\n", message);
120 exit(EXIT_FAILURE);
121 }
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123 The above code example is available pre‐packaged as the
124 explain_stime_or_die(3) function.
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126 explain_message_errno_stime
127 void explain_message_errno_stime(char *message, int message_size, int
128 errnum, time_t *t);
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130 The explain_message_errno_stime function is used to obtain an explana‐
131 tion of an error returned by the stime(2) system call. The least the
132 message will contain is the value of strerror(errno), but usually it
133 will do much better, and indicate the underlying cause in more detail.
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135 message The location in which to store the returned message. If a suit‐
136 able message return buffer is supplied, this function is thread
137 safe.
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139 message_size
140 The size in bytes of the location in which to store the
141 returned message.
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143 errnum The error value to be decoded, usually obtained from the errno
144 global variable just before this function is called. This is
145 necessary if you need to call any code between the system call
146 to be explained and this function, because many libc functions
147 will alter the value of errno.
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149 t The original t, exactly as passed to the stime(2) system call.
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151 Example: This function is intended to be used in a fashion similar to
152 the following example:
153 if (stime(t) < 0)
154 {
155 int err = errno;
156 char message[3000];
157 explain_message_errno_stime(message, sizeof(message), err,
158 t);
159 fprintf(stderr, "%s\n", message);
160 exit(EXIT_FAILURE);
161 }
162
163 The above code example is available pre‐packaged as the
164 explain_stime_or_die(3) function.
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167 stime(2)
168 set system time
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170 explain_stime_or_die(3)
171 set system time and report errors
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174 libexplain version 1.4
175 Copyright (C) 2009 Peter Miller
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179 explain_stime(3)