off_t(3type) - Man pages

off_t(3type)                                                       off_t(3type)

NAME
       off_t, off64_t, loff_t - file sizes

LIBRARY
       Standard C library (libc)

SYNOPSIS
       #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
       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
       off_t  POSIX.1-2008.

       off64_t
              GNU and some BSDs.

       loff_t Linux.

VERSIONS
       off_t  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
       copy_file_range(2),  llseek(2),  lseek(2),  mmap(2),   posix_fadvise(2),
       pread(2),   readahead(2),  sync_file_range(2),  truncate(2),  fseeko(3),
       lockf(3), lseek64(3), posix_fallocate(3), feature_test_macros(7)

Linux man-pages 6.9.1              2024-05-02                      off_t(3type)

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