getdents()函數 Unix/Linux

getdents - 獲得目錄項

內容簡介

#include <unistd.h>
#include <linux/types.h>
#include <linux/dirent.h>
#include <linux/unistd.h>
#include <errno.h>

int getdents(unsigned int fd, struct dirent *dirp, unsigned int count);

描述

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.

The system call getdents() reads several dirent structures from the directory pointed at by fd into the memory area pointed to by dirp. The parameter count is the size of the memory area.

The dirent structure is declared as follows:

struct dirent {
    long d_ino;                 /* inode number */
    off_t d_off;                /* offset to next dirent */
    unsigned short d_reclen;    /* length of this dirent */
    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 the start of the next dirent. d_reclen is the size of this entire dirent. d_name is a null-terminated filename.

This call supersedes readdir(2).

返回值

On success, the number of bytes read is returned. On end of directory, 0 is returned. On error, -1 is returned, and errno is set appropriately.

錯誤

標簽	描述
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.

遵循於

SVr4.

注意

Glibc does not provide a wrapper for this system call; call it using syscall(2).

另請參閱

readdir (2)