Manpages - readdir.2
Table of Contents
NAME
readdir - read directory entry
SYNOPSIS
#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.
DESCRIPTION
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 This page documents the bare kernel system call interface, which is superseded by *getdents*(2).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.
RETURN VALUE
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.
ERRORS
- EBADF
- Invalid file descriptor fd.
- EFAULT
- Argument points outside the calling process’s address space.
- EINVAL
- Result buffer is too small.
- ENOENT
- No such directory.
- ENOTDIR
- File descriptor does not refer to a directory.
CONFORMING TO
This system call is Linux-specific.
NOTES
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.
SEE ALSO
*getdents*(2), *readdir*(3)
COLOPHON
This page is part of release 5.13 of the Linux man-pages project. A description of the project, information about reporting bugs, and the latest version of this page, can be found at https://www.kernel.org/doc/man-pages/.