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/*
* Copyright 2015 Vincent Sanders <vince@netsurf-browser.org>
*
* This file is part of libnsutils.
*
* Licensed under the MIT License,
* http://www.opensource.org/licenses/mit-license.php
*/
/**
* \file
* Time related operations.
*/
#ifndef NSUTILS_UNISTD_H_
#define NSUTILS_UNISTD_H_
#include <unistd.h>
/**
* Perform a write operation at a specific offset
*
* This writes the data into the file specifid by teh file handle at teh given
* offset. The offset may be beyond the existing file extent.
*
* This provides a uniform interface to the pwrite operation without system
* specific implementation details.
*
* \note The write pointer on the fd may be moved by this operation which
* differs from the posix version.
*
* \param fd The file descriptor.
* \param buf The data to write.
* \param count The length of data in \a buf to write.
* \param offset The offset into the file to write the data.
* \return the number of bytes written or -1 on error and errno set.
*/
ssize_t nsu_pwrite(int fd, const void *buf, size_t count, off_t offset);
/**
* Perform a read from a specific offset.
*
* This provides a uniform interface to the POSIX pread operation without
* system specific implementation details.
*
* \note The read pointer on the fd may be moved by this operation which
* differs from the POSIX version.
*
* \param fd The file descriptor.
* \param buf The buffer to place the data into.
* \param count The length of data to read.
* \param offset The offset into the file to read the data from.
* \return the number of bytes read or -1 on error and errno set.
*/
ssize_t nsu_pread(int fd, void *buf, size_t count, off_t offset);
#endif
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