操作系统对文件路径长度的限制

诸如EXT3文件系统的实现并不对文件路径的长度做限制。

即便NTFS，限制也相对宽松很多。

但是，操作系统在设计时却加了些限制：

“The on-disk structures have no inherent limit. Particular drivers and may impose limits of their own, however. MS-DOS does not support full pathnames longer than 260 bytes for FAT12 and FAT16. Windows NT does not support full pathnames longer than 32,767 bytes for NTFS. Linux has a pathname limit of 4,096.”

Linux的路径长度限制为4096字节，文件名长路限制为255字节。

In linux-2.6.11/include/linux/limits.h
#define NAME_MAX 255 /* # chars in a file name */
#define PATH_MAX 4096 /* # chars in a path name including nul */

（估计这里指的char字符，不是unicode字符。该点需要验证）

MSDN上也写到Windows API对文件路径的限制为260个字符（应该是Unicode字符，即中文占一个字节）。