Linux下定義了文件名長度及路徑名長度限制，具體在文件/usr/include/linux/limits.h中：
#ifndef _LINUX_LIMITS_H
#define _LINUX_LIMITS_H
#define NR_OPEN 1024
#define NGROUPS_MAX 65536 /* supplemental group IDs are available */
#define ARG_MAX 131072 /* # bytes of args + environ for exec() */
#define LINK_MAX 127 /* # links a file may have */
#define MAX_CANON 255 /* size of the canonical input queue */
#define MAX_INPUT 255 /* size of the type-ahead buffer */
#define NAME_MAX 255 /* # chars in a file name */
#define PATH_MAX 4096 /* # chars in a path name including nul */
#define PIPE_BUF 4096 /* # bytes in atomic write to a pipe */
#define XATTR_NAME_MAX 255 /* # chars in an extended attribute name */
#define XATTR_SIZE_MAX 65536 /* size of an extended attribute value (64k) */
#define XATTR_LIST_MAX 65536 /* size of extended attribute namelist (64k) */
#define RTSIG_MAX 32
#endif
可以看到路徑名長度為4096個字符(包括nul結尾)沪伙，而文件名長度為255個字符办素。
