#include "v3p_f2c.h"
#include "fio.h"
#ifdef __cplusplus
extern "C" {
#endif
#ifdef KR_headers
integer f_rew(a) alist *a;
#else
integer f_rew(alist *a)
#endif
{
        unit *b;
        if(a->aunit>=MXUNIT || a->aunit<0)
                err(a->aerr,101,"rewind");
        b = &f__units[a->aunit];
        if(b->ufd == NULL || b->uwrt == 3)
                return(0);
        if(!b->useek)
                err(a->aerr,106,"rewind")
        if(b->uwrt) {
                (void) t_runc(a);
                b->uwrt = 3;
                }
        rewind(b->ufd);
        b->uend=0;
        return(0);
}
#ifdef __cplusplus
}
#endif
