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#ifndef GMX_FILEIO_XTCIO_H
#define GMX_FILEIO_XTCIO_H

#include <filesystem>

#include "gromacs/math/vectypes.h"
#include "gromacs/utility/basedefinitions.h"
#include "gromacs/utility/real.h"

struct t_fileio;

/* All functions return 1 if successful, 0 otherwise
 * bOK tells if a frame is not corrupted
 */

/* Note that XTC was implemented to use xdr_int for the step number,
 * which is defined by the standard to be signed and 32 bit. We didn't
 * design the format to be extensible, so we can't fix the fact that
 * after 2^31 frames, step numbers will wrap to be
 * negative. Fortunately, this tends not to cause serious problems,
 * and we've fixed it in TNG. */

struct t_fileio* open_xtc(const std::filesystem::path& filename, const char* mode);
/* Open a file for xdr I/O */

void close_xtc(struct t_fileio* fio);
/* Close the file for xdr I/O */

int read_first_xtc(struct t_fileio* fio,
                   int*             natoms,
                   int64_t*         step,
                   real*            time,
                   matrix           box,
                   rvec**           x,
                   real*            prec,
                   gmx_bool*        bOK);
/* Open xtc file, read xtc file first time, allocate memory for x */

int read_next_xtc(struct t_fileio* fio, int natoms, int64_t* step, real* time, matrix box, rvec* x, real* prec, gmx_bool* bOK);
/* Read subsequent frames */

int write_xtc(struct t_fileio* fio, int natoms, int64_t step, real time, const rvec* box, const rvec* x, real prec);
/* Write a frame to xtc file */

#endif
