off_t(3type) - Linux manual page (original) (raw)

offt(3type) offt(3type)

NAME top

   off_t, off64_t, loff_t - file sizes

LIBRARY top

   Standard C library (_libc_)

SYNOPSIS top

   **#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;**

DESCRIPTION top

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

   _off64t_ is a 64-bit version of the type, used in glibc.

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

STANDARDS top

   _offt_  POSIX.1-2008.

   _off64t_
          GNU and some BSDs.

   _lofft_ Linux.

VERSIONS top

   _offt_  POSIX.1-2001.

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

NOTES top

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

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

SEE ALSO top

   [copy_file_range(2)](../man2/copy%5Ffile%5Frange.2.html), [llseek(2)](../man2/llseek.2.html), [lseek(2)](../man2/lseek.2.html), [mmap(2)](../man2/mmap.2.html),
   [posix_fadvise(2)](../man2/posix%5Ffadvise.2.html), [pread(2)](../man2/pread.2.html), [readahead(2)](../man2/readahead.2.html), [sync_file_range(2)](../man2/sync%5Ffile%5Frange.2.html),
   [truncate(2)](../man2/truncate.2.html), [fseeko(3)](../man3/fseeko.3.html), [lockf(3)](../man3/lockf.3.html), [lseek64(3)](../man3/lseek64.3.html), [posix_fallocate(3)](../man3/posix%5Ffallocate.3.html),
   [feature_test_macros(7)](../man7/feature%5Ftest%5Fmacros.7.html)

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Linux man-pages 6.10 2024-05-02 offt(3type)