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readdir(2) [centos man page]

READDIR(2)						     Linux Programmer's Manual							READDIR(2)

NAME
readdir - read directory entry SYNOPSIS
int readdir(unsigned int fd, struct old_linux_dirent *dirp, unsigned int count); Note: There is no glibc wrapper for this system call; 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 This page documents the bare kernel system call interface, which is superseded by getdents(2).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 as follows: struct old_linux_dirent { long d_ino; /* inode number */ off_t d_off; /* offset to this old_linux_dirent */ unsigned short d_reclen; /* length of this d_name */ char d_name[NAME_MAX+1]; /* filename (null-terminated) */ } d_ino is an inode number. d_off 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 (''). 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 appropriately. 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
Glibc does not provide a wrapper for this system call; call it using syscall(2). 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 3.53 of the Linux man-pages project. A description of the project, and information about reporting bugs, can be found at http://www.kernel.org/doc/man-pages/. Linux 2013-06-21 READDIR(2)

Check Out this Related Man Page

READDIR(2)						     Linux Programmer's Manual							READDIR(2)

NAME
readdir - read directory entry SYNOPSIS
int readdir(unsigned int fd, struct old_linux_dirent *dirp, unsigned int count); 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 as follows: struct old_linux_dirent { long d_ino; /* inode number */ off_t d_off; /* offset to this old_linux_dirent */ unsigned short d_reclen; /* length of this d_name */ char d_name[NAME_MAX+1]; /* filename (null-terminated) */ } d_ino is an inode number. d_off 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 null terminator. 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 appropriately. 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
Glibc does not provide a wrapper for this system call; call it using syscall(2). You will need to define the old_linux_dirent structure yourself. SEE ALSO
getdents(2), readdir(3) COLOPHON
This page is part of release 3.25 of the Linux man-pages project. A description of the project, and information about reporting bugs, can be found at http://www.kernel.org/doc/man-pages/. Linux 2008-10-02 READDIR(2)

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