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off64_t

(3type)

file sizes

Library functionsmanpages-dev 6.9.1-1also documents off_t, loff_t
#include <sys/types.h> typedef /* ... */ off_t; #define _LARGEFILE64_SOURCE #include <sys/types.h> typedef /* ... */ off64_t; #define _GNU_SOURCE #include <sys/types.h> typedef /* ... */ loff_t;

LIBRARY

Standard C library (libc)

DESCRIPTION

off_t is used for describing file sizes. It is a signed integer type.

off64_t is a 64-bit version of the type, used in glibc.

loff_t is a 64-bit version of the type, introduced by the Linux kernel.

STANDARDS

POSIX.1-2008.
GNU and some BSDs.
Linux.

VERSIONS

POSIX.1-2001.

<aio.h> and <stdio.h> define off_t since POSIX.1-2008.

NOTES

On some architectures, the width of off_t can be controlled with the feature test macro _FILE_OFFSET_BITS.

The following headers also provide off_t: <aio.h>, <fcntl.h>, <stdio.h>, <sys/mman.h>, <sys/stat.h>, and <unistd.h>.

See also