Copyright © tutorialspoint.com

# llseek() - Unix, Linux System Call

# NAME

_llseek - reposition read/write file offset

# SYNOPSIS

    #include <sys/types.h>
    #include <unistd.h>

    int _llseek(unsigned int fd, unsigned long offset_high,
                unsigned long offset_low, loff_t *result,
                unsigned int whence);

# DESCRIPTION

The _llseek() function repositions the offset of the open file associated with the file descriptor fd to (offset_high<<32) | offset_low bytes relative to the beginning of the file, the current position in the file, or the end of the file, depending on whether whence is SEEK_SET, SEEK_CUR, or SEEK_END, respectively. It returns the resulting file position in the argument result.

# RETURN VALUE

Upon successful completion, _llseek() returns 0. Otherwise, a value of -1 is returned and errno is set to indicate the error.

# ERRORS

Tag | Description
--- | ---
EBADF | fd is not an open file descriptor.
EFAULT | Problem with copying results to user space.
EINVAL | whence is invalid.

# CONFORMING TO

This function is Linux specific, and should not be used in programs intended to be portable.

# NOTES

Glibc does not provide a wrapper for this system call; call it using syscall(2).

# SEE ALSO

- lseek (2)

Copyright © tutorialspoint.com