readdir − read directory entry
Standard C library (libc, −lc)
#include
<sys/syscall.h> /* Definition of SYS_*
constants */
#include <unistd.h>
int
syscall(SYS_readdir, unsigned int fd,
struct old_linux_dirent *dirp, unsigned
int count);
Note: There is no definition of struct old_linux_dirent; see NOTES.
This is not the function you are interested in. Look at readdir(3) for the POSIX conforming C library interface. This page documents the bare kernel system call interface, which is superseded by getdents(2).
readdir() reads one old_linux_dirent structure from the directory referred to by the file descriptor fd into the buffer pointed to by dirp. The argument count is ignored; at most one old_linux_dirent structure is read.
The old_linux_dirent structure is declared (privately in Linux kernel file fs/readdir.c) as follows:
struct
old_linux_dirent {
unsigned long d_ino; /* inode number */
unsigned long d_offset; /* offset to this
old_linux_dirent */
unsigned short d_namlen; /* length of this d_name */
char d_name[1]; /* filename (null−terminated) */
}
d_ino is an inode number. d_offset is the distance from the start of the directory to this old_linux_dirent. d_reclen is the size of d_name, not counting the terminating null byte ('\0'). d_name is a null-terminated filename.
On success, 1 is returned. On end of directory, 0 is returned. On error, −1 is returned, and errno is set to indicate the error.
EBADF |
Invalid file descriptor fd. |
|||
EFAULT |
Argument points outside the calling process’s address space. |
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EINVAL |
Result buffer is too small. |
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ENOENT |
No such directory. |
ENOTDIR
File descriptor does not refer to a directory.
You will need to define the old_linux_dirent structure yourself. However, probably you should use readdir(3) instead.
This system call does not exist on x86-64.
Linux.
getdents(2), readdir(3)