Path Field Limits


#include <stdlib.h>


These constants define the maximum length for the path and for the individual fields within the path.

Constant Meaning
_MAX_DIR Maximum length of directory component
_MAX_DRIVE Maximum length of drive component
_MAX_EXT Maximum length of extension component
_MAX_FNAME Maximum length of filename component
_MAX_PATH Maximum length of full path


The C Runtime supports path lengths up to 32768 characters in length, but it is up to the operating system, specifically the file system, to support these longer paths. The sum of the fields should not exceed _MAX_PATH for full backwards compatibility with FAT32 file systems. The Windows NTFS file system supports paths up to 32768 characters in length, but only when using the Unicode APIs. When using long path names, prefix the path with the characters \\?\ and use the Unicode versions of the C Runtime functions.

See also

Global Constants