1explain_acl_set_fd(3) Library Functions Manual explain_acl_set_fd(3)
2
6 explain_acl_set_fd - explain acl_set_fd(3) errors
7
9 #include <libexplain/acl_set_fd.h>
10 const char *explain_acl_set_fd(int fildes, acl_t acl);
11 const char *explain_errno_acl_set_fd(int errnum, int fildes, acl_t
12 acl);
13 void explain_message_acl_set_fd(char *message, int message_size, int
14 fildes, acl_t acl);
15 void explain_message_errno_acl_set_fd(char *message, int message_size,
16 int errnum, int fildes, acl_t acl);
17
19 These functions may be used to obtain explanations for errors returned
20 by the acl_set_fd(3) system call.
21 explain_acl_set_fd
23 const char *explain_acl_set_fd(int fildes, acl_t acl);
24 The explain_acl_set_fd function is used to obtain an explanation of an
26 error returned by the acl_set_fd(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 acl_set_fd(3)
34 system call.
35 acl The original acl, exactly as passed to the acl_set_fd(3) system
37 call.
38 Returns:
40 The message explaining the error. This message buffer is shared
41 by all libexplain functions which do not supply a buffer in
42 their argument list. This will be overwritten by the next call
43 to any libexplain function which shares this buffer, including
44 other threads.
45 Note: This function is not thread safe, because it shares a return buf‐
47 fer across all threads, and many other functions in this library.
48 Example: This function is intended to be used in a fashion similar to
50 the following example:
51 if (acl_set_fd(fildes, acl) < 0)
52 {
53 fprintf(stderr, "%s\n", explain_acl_set_fd(fildes, acl));
54 exit(EXIT_FAILURE);
55 }
56 The above code example is available pre-packaged as the
58 explain_acl_set_fd_or_die(3) function.
59 explain_errno_acl_set_fd
61 const char *explain_errno_acl_set_fd(int errnum, int fildes, acl_t
62 acl);
63 The explain_errno_acl_set_fd function is used to obtain an explanation
65 of an error returned by the acl_set_fd(3) system call. The least the
66 message will contain is the value of strerror(errno), but usually it
67 will do much better, and indicate the underlying cause in more detail.
68 errnum The error value to be decoded, usually obtained from the errno
70 global variable just before this function is called. This is
71 necessary if you need to call any code between the system call
72 to be explained and this function, because many libc functions
73 will alter the value of errno.
74 fildes The original fildes, exactly as passed to the acl_set_fd(3)
76 system call.
77 acl The original acl, exactly as passed to the acl_set_fd(3) system
79 call.
80 Returns:
82 The message explaining the error. This message buffer is shared
83 by all libexplain functions which do not supply a buffer in
84 their argument list. This will be overwritten by the next call
85 to any libexplain function which shares this buffer, including
86 other threads.
87 Note: This function is not thread safe, because it shares a return buf‐
89 fer across all threads, and many other functions in this library.
90 Example: This function is intended to be used in a fashion similar to
92 the following example:
93 if (acl_set_fd(fildes, acl) < 0)
94 {
95 int err = errno;
96 fprintf(stderr, "%s\n", explain_errno_acl_set_fd(err,
97 fildes, acl));
98 exit(EXIT_FAILURE);
99 }
100 The above code example is available pre-packaged as the
102 explain_acl_set_fd_or_die(3) function.
103 explain_message_acl_set_fd
105 void explain_message_acl_set_fd(char *message, int message_size, int
106 fildes, acl_t acl);
107 The explain_message_acl_set_fd function is used to obtain an explana‐
109 tion of an error returned by the acl_set_fd(3) system call. The least
110 the message will contain is the value of strerror(errno), but usually
111 it will do much better, and indicate the underlying cause in more
112 detail.
113 The errno global variable will be used to obtain the error value to be
115 decoded.
116 message The location in which to store the returned message. If a suit‐
118 able message return buffer is supplied, this function is thread
119 safe.
120 message_size
122 The size in bytes of the location in which to store the
123 returned message.
124 fildes The original fildes, exactly as passed to the acl_set_fd(3)
126 system call.
127 acl The original acl, exactly as passed to the acl_set_fd(3) system
129 call.
130 Example: This function is intended to be used in a fashion similar to
132 the following example:
133 if (acl_set_fd(fildes, acl) < 0)
134 {
135 char message[3000];
136 explain_message_acl_set_fd(message, sizeof(message), fildes,
137 acl);
138 fprintf(stderr, "%s\n", message);
139 exit(EXIT_FAILURE);
140 }
141 The above code example is available pre-packaged as the
143 explain_acl_set_fd_or_die(3) function.
144 explain_message_errno_acl_set_fd
146 void explain_message_errno_acl_set_fd(char *message, int message_size,
147 int errnum, int fildes, acl_t acl);
148 The explain_message_errno_acl_set_fd function is used to obtain an
150 explanation of an error returned by the acl_set_fd(3) system call. The
151 least the message will contain is the value of strerror(errno), but
152 usually it will do much better, and indicate the underlying cause in
153 more detail.
154 message The location in which to store the returned message. If a suit‐
156 able message return buffer is supplied, this function is thread
157 safe.
158 message_size
160 The size in bytes of the location in which to store the
161 returned message.
162 errnum The error value to be decoded, usually obtained from the errno
164 global variable just before this function is called. This is
165 necessary if you need to call any code between the system call
166 to be explained and this function, because many libc functions
167 will alter the value of errno.
168 fildes The original fildes, exactly as passed to the acl_set_fd(3)
170 system call.
171 acl The original acl, exactly as passed to the acl_set_fd(3) system
173 call.
174 Example: This function is intended to be used in a fashion similar to
176 the following example:
177 if (acl_set_fd(fildes, acl) < 0)
178 {
179 int err = errno;
180 char message[3000];
181 explain_message_errno_acl_set_fd(message, sizeof(message),
182 err, fildes, acl);
183 fprintf(stderr, "%s\n", message);
184 exit(EXIT_FAILURE);
185 }
186 The above code example is available pre-packaged as the
188 explain_acl_set_fd_or_die(3) function.
189
191 acl_set_fd(3)
192 set an ACL by file descriptor
193 explain_acl_set_fd_or_die(3)
195 set an ACL by file descriptor and report errors
196
198 libexplain version 1.4
199 Copyright (C) 2013 Peter Miller
200 explain_acl_set_fd(3)