1explain_futimes(3) Library Functions Manual explain_futimes(3)
2
6 explain_futimes - explain futimes(3) errors
7
9 #include <libexplain/futimes.h>
10 const char *explain_futimes(int fildes, const struct timeval *tv);
11 const char *explain_errno_futimes(int errnum, int fildes, const struct
12 timeval *tv);
13 void explain_message_futimes(char *message, int message_size, int
14 fildes, const struct timeval *tv);
15 void explain_message_errno_futimes(char *message, int message_size, int
16 errnum, int fildes, const struct timeval *tv);
17
19 These functions may be used to obtain explanations for errors returned
20 by the futimes(3) system call.
21 explain_futimes
23 const char *explain_futimes(int fildes, const struct timeval *tv);
24 The explain_futimes function is used to obtain an explanation of an
26 error returned by the futimes(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 This function is intended to be used in a fashion similar to the fol‐
34 lowing example:
35 if (futimes(fildes, tv) < 0)
36 {
37 fprintf(stderr, "%s\n", explain_futimes(fildes, tv));
38 exit(EXIT_FAILURE);
39 }
40 The above code example is available pre‐packaged as the
42 explain_futimes_or_die(3) function.
43 fildes The original fildes, exactly as passed to the futimes(3) system
45 call.
46 tv The original tv, exactly as passed to the futimes(3) system
48 call.
49 Returns:
51 The message explaining the error. This message buffer is
52 shared by all libexplain functions which do not supply a buffer
53 in their argument list. This will be overwritten by the next
54 call to any libexplain function which shares this buffer,
55 including other threads.
56 Note: This function is not thread safe, because it shares a return buf‐
58 fer across all threads, and many other functions in this library.
59 explain_errno_futimes
61 const char *explain_errno_futimes(int errnum, int fildes, const struct
62 timeval *tv);
63 The explain_errno_futimes function is used to obtain an explanation of
65 an error returned by the futimes(3) system call. The least the message
66 will contain is the value of strerror(errnum), but usually it will do
67 much better, and indicate the underlying cause in more detail.
68 This function is intended to be used in a fashion similar to the fol‐
70 lowing example:
71 if (futimes(fildes, tv) < 0)
72 {
73 int err = errno;
74 fprintf(stderr, "%s\n", explain_errno_futimes(err, fildes, tv));
75 exit(EXIT_FAILURE);
76 }
77 The above code example is available pre‐packaged as the
79 explain_futimes_or_die(3) function.
80 errnum The error value to be decoded, usually obtained from the errno
82 global variable just before this function is called. This is
83 necessary if you need to call any code between the system call
84 to be explained and this function, because many libc functions
85 will alter the value of errno.
86 fildes The original fildes, exactly as passed to the futimes(3) system
88 call.
89 tv The original tv, exactly as passed to the futimes(3) system
91 call.
92 Returns:
94 The message explaining the error. This message buffer is
95 shared by all libexplain functions which do not supply a buffer
96 in their argument list. This will be overwritten by the next
97 call to any libexplain function which shares this buffer,
98 including other threads.
99 Note: This function is not thread safe, because it shares a return buf‐
101 fer across all threads, and many other functions in this library.
102 explain_message_futimes
104 void explain_message_futimes(char *message, int message_size, int
105 fildes, const struct timeval *tv);
106 The explain_message_futimes function may be used to obtain an explana‐
108 tion of an error returned by the futimes(3) system call. The least the
109 message will contain is the value of strerror(errno), but usually it
110 will do much better, and indicate the underlying cause in more detail.
111 The errno global variable will be used to obtain the error value to be
113 decoded.
114 This function is intended to be used in a fashion similar to the fol‐
116 lowing example:
117 if (futimes(fildes, tv) < 0)
118 {
119 char message[3000];
120 explain_message_futimes(message, sizeof(message), fildes, tv);
121 fprintf(stderr, "%s\n", message);
122 exit(EXIT_FAILURE);
123 }
124 The above code example is available pre‐packaged as the
126 explain_futimes_or_die(3) function.
127 message The location in which to store the returned message. If a
129 suitable message return buffer is supplied, this function is
130 thread safe.
131 message_size
133 The size in bytes of the location in which to store the
134 returned message.
135 fildes The original fildes, exactly as passed to the futimes(3) system
137 call.
138 tv The original tv, exactly as passed to the futimes(3) system
140 call.
141 explain_message_errno_futimes
143 void explain_message_errno_futimes(char *message, int message_size, int
144 errnum, int fildes, const struct timeval *tv);
145 The explain_message_errno_futimes function may be used to obtain an
147 explanation of an error returned by the futimes(3) system call. The
148 least the message will contain is the value of strerror(errnum), but
149 usually it will do much better, and indicate the underlying cause in
150 more detail.
151 This function is intended to be used in a fashion similar to the fol‐
153 lowing example:
154 if (futimes(fildes, tv) < 0)
155 {
156 int err = errno;
157 char message[3000];
158 explain_message_errno_futimes(message, sizeof(message), err, fildes, tv);
159 fprintf(stderr, "%s\n", message);
160 exit(EXIT_FAILURE);
161 }
162 The above code example is available pre‐packaged as the
164 explain_futimes_or_die(3) function.
165 message The location in which to store the returned message. If a
167 suitable message return buffer is supplied, this function is
168 thread safe.
169 message_size
171 The size in bytes of the location in which to store the
172 returned message.
173 errnum The error value to be decoded, usually obtained from the errno
175 global variable just before this function is called. This is
176 necessary if you need to call any code between the system call
177 to be explained and this function, because many libc functions
178 will alter the value of errno.
179 fildes The original fildes, exactly as passed to the futimes(3) system
181 call.
182 tv The original tv, exactly as passed to the futimes(3) system
184 call.
185
187 futimes(3)
188 change file timestamps
189 explain_futimes_or_die(3)
191 change file timestamps and report errors
192
194 libexplain version 1.4
195 Copyright (C) 2008 Peter Miller
196 explain_futimes(3)