path-field-limits.md

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Learn more about: Path Field Limits	Path Field Limits	11/04/2016	_MAX_EXT _MAX_DIR _MAX_PATH _MAX_FNAME _MAX_DRIVE STDLIB/_MAX_EXT STDLIB/_MAX_DIR STDLIB/_MAX_PATH STDLIB/_MAX_FNAME STDLIB/_MAX_DRIVE	path field constants MAX_FNAME constant _MAX_DIR constant _MAX_DRIVE constant paths, maximum limit _MAX_PATH constant MAX_DRIVE constant _MAX_FNAME constant _MAX_EXT constant MAX_DIR constant MAX_EXT constant	2b5d0e43-1347-45b4-8397-24a8a45c444e

Path field limits

Syntax

#include <stdlib.h>

Remarks

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

Note

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