lseek64(3) — Linux manual page

lseek64(3)               Library Functions Manual              lseek64(3)

NAME         top

       lseek64 - reposition 64-bit read/write file offset

LIBRARY         top

       Standard C library (libc, -lc)

SYNOPSIS         top

       #define _LARGEFILE64_SOURCE     /* See feature_test_macros(7) */
       #include <sys/types.h>
       #include <unistd.h>

       [[deprecated]] off64_t lseek64(int fd, off64_t offset, int whence);

DESCRIPTION         top

       This function is equivalent to lseek(2) if one compiles with

           #define _FILE_OFFSET_BITS 64

       Use lseek(2) instead.

ATTRIBUTES         top

       For an explanation of the terms used in this section, see
       attributes(7).
       ┌──────────────────────────────────────┬───────────────┬─────────┐
       │ Interface                            │ Attribute     │ Value   │
       ├──────────────────────────────────────┼───────────────┼─────────┤
       │ lseek64()                            │ Thread safety │ MT-Safe │
       └──────────────────────────────────────┴───────────────┴─────────┘

HISTORY         top

       glibc 2.1.

       lseek64() is one of the functions that was specified in the Large
       File Summit (LFS) specification that was completed in 1996.  The
       purpose of the specification was to provide transitional support
       that allowed applications on 32-bit systems to access files whose
       size exceeds that which can be represented with a 32-bit off_t
       type.

SEE ALSO         top

       _llseek(2), lseek(2)

COLOPHON         top

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Linux man-pages 6.19            2026-06-13                     lseek64(3)

Pages that refer to this page: llseek(3)

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