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28 .\" @(#)getdirentries.2 8.2 (Berkeley) 5/3/95
37 .Nd "get directory entries in a file system independent format"
44 .Fn getdirentries "int fd" "char *buf" "size_t nbytes" "off_t *basep"
46 .Fn getdents "int fd" "char *buf" "size_t nbytes"
52 system calls read directory entries from the directory
53 referenced by the file descriptor
55 into the buffer pointed to by
57 in a file system independent format.
60 of data will be transferred.
63 argument must be greater than or equal to the
64 block size associated with the file,
67 Some file systems may not support these system calls
68 with buffers smaller than this size.
70 The data in the buffer is a series of
72 structures each containing the following entries:
73 .Bd -literal -offset indent
79 char d_name[MAXNAMLEN + 1]; /* see below */
84 entry is a number which is unique for each
85 distinct file in the file system.
86 Files that are linked by hard links (see
92 field returns a cookie which can be used with
94 to position the directory descriptor to the next entry.
97 entry is the length, in bytes, of the directory record.
100 entry is the type of the file pointed to by the directory record.
101 The file type values are defined in
105 entry contains a null terminated file name.
108 entry specifies the length of the file name excluding the null byte.
109 Thus the actual size of
115 Entries may be separated by extra space.
118 entry may be used as an offset from the start of a
120 structure to the next structure, if any.
122 The actual number of bytes transferred is returned.
123 The current position pointer associated with
125 is set to point to the next block of entries.
126 The pointer may not advance by the number of bytes returned by
130 A value of zero is returned when
131 the end of the directory has been reached.
135 pointer value is non-NULL ,
138 system call writes the position of the block read into the location pointed to by
140 Alternatively, the current position pointer may be set and retrieved by
142 The current position pointer should only be set to a value returned by
144 a value returned in the location pointed to by
149 a value returned in the
153 .Sh IMPLEMENTATION NOTES
156 field is being used as a cookie to readdir for nfs servers.
157 These cookies can be cached and allow to read directory entries at a specific
160 If successful, the number of bytes actually transferred is returned.
161 Otherwise, -1 is returned and the global variable
163 is set to indicate the error.
174 is not a valid file descriptor open for reading.
180 point outside the allocated address space.
182 The file referenced by
184 is not a directory, or
186 is too small for returning a directory entry or block of entries,
187 or the current position pointer is invalid.
191 error occurred while reading from or writing to the file system.
193 Corrupted data was detected while reading from the file system.
201 system call first appeared in
205 system call first appeared in