#include "v3p_f2c.h"
#include "fio.h"
#ifdef __cplusplus
extern "C" {
#endif

 int
#ifdef KR_headers
c_due(a) cilist *a;
#else
c_due(cilist *a)
#endif
{
        if(!f__init) f_init();
        f__sequential=f__formatted=f__recpos=0;
        f__external=1;
        f__curunit = &f__units[a->ciunit];
        if(a->ciunit>=MXUNIT || a->ciunit<0)
                err(a->cierr,101,"startio");
        f__elist=a;
        if(f__curunit->ufd==NULL && fk_open(DIR,UNF,a->ciunit) ) err(a->cierr,104,"due");
        f__cf=f__curunit->ufd;
        if(f__curunit->ufmt) err(a->cierr,102,"cdue")
        if(!f__curunit->useek) err(a->cierr,104,"cdue")
        if(f__curunit->ufd==NULL) err(a->cierr,114,"cdue")
        if(a->cirec <= 0)
                err(a->cierr,130,"due")
        FSEEK(f__cf,(OFF_T)(a->cirec-1)*f__curunit->url,SEEK_SET);
        f__curunit->uend = 0;
        return(0);
}
#ifdef KR_headers
integer s_rdue(a) cilist *a;
#else
integer s_rdue(cilist *a)
#endif
{
        int n;
        f__reading=1;
        if(n=c_due(a)) return(n);
        if(f__curunit->uwrt && f__nowreading(f__curunit))
                err(a->cierr,errno,"read start");
        return(0);
}
#ifdef KR_headers
integer s_wdue(a) cilist *a;
#else
integer s_wdue(cilist *a)
#endif
{
        int n;
        f__reading=0;
        if(n=c_due(a)) return(n);
        if(f__curunit->uwrt != 1 && f__nowwriting(f__curunit))
                err(a->cierr,errno,"write start");
        return(0);
}
integer e_rdue(Void)
{
        if(f__curunit->url==1 || f__recpos==f__curunit->url)
                return(0);
        FSEEK(f__cf,(OFF_T)(f__curunit->url-f__recpos),SEEK_CUR);
        if(FTELL(f__cf)%f__curunit->url)
                err(f__elist->cierr,200,"syserr");
        return(0);
}
integer e_wdue(Void)
{
#ifdef ALWAYS_FLUSH
        if (fflush(f__cf))
                err(f__elist->cierr,errno,"write end");
#endif
        return(e_rdue());
}
#ifdef __cplusplus
}
#endif
