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/**
* \file get.c
*
* \brief Get segment routines.
*
* This program is free software under the GNU General Public License
* (>=v2). Read the file COPYING that comes with GRASS for details.
*
* \author GRASS GIS Development Team
*
* \date 2005-2006
*/
#include <string.h>
#include <grass/segment.h>
/*bugfix: buf: char* vs int* -> wrong pointer arithmetics!!!. Pierre de Mouveaux - 09 april 2000 */
/* int segment_get (SEGMENT *SEG, register int *buf,int row,int col) */
/**
* \fn int segment_get (SEGMENT *SEG, void *buf, int row, int col)
*
* \brief Get value from segment file.
*
* Provides random read access to the segmented data. It gets
* <i>len</i> bytes of data into <b>buf</b> from the segment file
* <b>seg</b> for the corresponding <b>row</b> and <b>col</b> in the
* original data matrix.
*
* \param[in] seg segment
* \param[in,out] buf value return buffer
* \param[in] row
* \param[in] col
* \return 1 of successful
* \return -1 if unable to seek or read segment file
*/
int segment_get(SEGMENT * SEG, void *buf, int row, int col)
{
int index, n, i;
segment_address(SEG, row, col, &n, &index);
if ((i = segment_pagein(SEG, n)) < 0)
return -1;
memcpy(buf, &SEG->scb[i].buf[index], SEG->len);
return 1;
}
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