1explain_mkstemp(3) Library Functions Manual explain_mkstemp(3)
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6 explain_mkstemp - explain mkstemp(3) errors
7
9 #include <libexplain/mkstemp.h>
10 const char *explain_mkstemp(char *template);
11 const char *explain_errno_mkstemp(int errnum, char *template);
12 void explain_message_mkstemp(char *message, int message_size, char
13 *template);
14 void explain_message_errno_mkstemp(char *message, int message_size, int
15 errnum, char *template);
16
18 These functions may be used to obtain explanations for errors returned
19 by the mkstemp(3) system call.
20 explain_mkstemp
22 const char *explain_mkstemp(char *template);
23 The explain_mkstemp function is used to obtain an explanation of an
25 error returned by the mkstemp(3) system call. The least the message
26 will contain is the value of strerror(errno), but usually it will do
27 much better, and indicate the underlying cause in more detail.
28 The errno global variable will be used to obtain the error value to be
30 decoded.
31 template
33 The original template, exactly as passed to the mkstemp(3) sys‐
34 tem call.
35 Returns:
37 The message explaining the error. This message buffer is shared
38 by all libexplain functions which do not supply a buffer in
39 their argument list. This will be overwritten by the next call
40 to any libexplain function which shares this buffer, including
41 other threads.
42 Note: This function is not thread safe, because it shares a return buf‐
44 fer across all threads, and many other functions in this library.
45 Example: This function is intended to be used in a fashion similar to
47 the following example:
48 int result = mkstemp(template);
49 if (result < 0)
50 {
51 fprintf(stderr, "%s\n", explain_mkstemp(template));
52 exit(EXIT_FAILURE);
53 }
54 The above code example is available pre‐packaged as the
56 explain_mkstemp_or_die(3) function.
57 explain_errno_mkstemp
59 const char *explain_errno_mkstemp(int errnum, char *template);
60 The explain_errno_mkstemp function is used to obtain an explanation of
62 an error returned by the mkstemp(3) system call. The least the message
63 will contain is the value of strerror(errno), but usually it will do
64 much better, and indicate the underlying cause in more detail.
65 errnum The error value to be decoded, usually obtained from the errno
67 global variable just before this function is called. This is
68 necessary if you need to call any code between the system call
69 to be explained and this function, because many libc functions
70 will alter the value of errno.
71 template
73 The original template, exactly as passed to the mkstemp(3) sys‐
74 tem call.
75 Returns:
77 The message explaining the error. This message buffer is shared
78 by all libexplain functions which do not supply a buffer in
79 their argument list. This will be overwritten by the next call
80 to any libexplain function which shares this buffer, including
81 other threads.
82 Note: This function is not thread safe, because it shares a return buf‐
84 fer across all threads, and many other functions in this library.
85 Example: This function is intended to be used in a fashion similar to
87 the following example:
88 int result = mkstemp(template);
89 if (result < 0)
90 {
91 int err = errno;
92 fprintf(stderr, "%s\n", explain_errno_mkstemp(err, tem‐
93 plate));
94 exit(EXIT_FAILURE);
95 }
96 The above code example is available pre‐packaged as the
98 explain_mkstemp_or_die(3) function.
99 explain_message_mkstemp
101 void explain_message_mkstemp(char *message, int message_size, char
102 *template);
103 The explain_message_mkstemp function is used to obtain an explanation
105 of an error returned by the mkstemp(3) system call. The least the mes‐
106 sage will contain is the value of strerror(errno), but usually it will
107 do much better, and indicate the underlying cause in more detail.
108 The errno global variable will be used to obtain the error value to be
110 decoded.
111 message The location in which to store the returned message. If a suit‐
113 able message return buffer is supplied, this function is thread
114 safe.
115 message_size
117 The size in bytes of the location in which to store the
118 returned message.
119 template
121 The original template, exactly as passed to the mkstemp(3) sys‐
122 tem call.
123 Example: This function is intended to be used in a fashion similar to
125 the following example:
126 int result = mkstemp(template);
127 if (result < 0)
128 {
129 char message[3000];
130 explain_message_mkstemp(message, sizeof(message), template);
131 fprintf(stderr, "%s\n", message);
132 exit(EXIT_FAILURE);
133 }
134 The above code example is available pre‐packaged as the
136 explain_mkstemp_or_die(3) function.
137 explain_message_errno_mkstemp
139 void explain_message_errno_mkstemp(char *message, int message_size, int
140 errnum, char *template);
141 The explain_message_errno_mkstemp function is used to obtain an expla‐
143 nation of an error returned by the mkstemp(3) system call. The least
144 the message will contain is the value of strerror(errno), but usually
145 it will do much better, and indicate the underlying cause in more
146 detail.
147 message The location in which to store the returned message. If a suit‐
149 able message return buffer is supplied, this function is thread
150 safe.
151 message_size
153 The size in bytes of the location in which to store the
154 returned message.
155 errnum The error value to be decoded, usually obtained from the errno
157 global variable just before this function is called. This is
158 necessary if you need to call any code between the system call
159 to be explained and this function, because many libc functions
160 will alter the value of errno.
161 template
163 The original template, exactly as passed to the mkstemp(3) sys‐
164 tem call.
165 Example: This function is intended to be used in a fashion similar to
167 the following example:
168 int result = mkstemp(template);
169 if (result < 0)
170 {
171 int err = errno;
172 char message[3000];
173 explain_message_errno_mkstemp(message, sizeof(message), err,
174 template);
175 fprintf(stderr, "%s\n", message);
176 exit(EXIT_FAILURE);
177 }
178 The above code example is available pre‐packaged as the
180 explain_mkstemp_or_die(3) function.
181
183 mkstemp(3)
184 create a unique temporary file
185 explain_mkstemp_or_die(3)
187 create a unique temporary file and report errors
188
190 libexplain version 0.40
191 Copyright (C) 2009 Peter Miller
192 explain_mkstemp(3)