usr/src/libI77/sue.c

#include "fio.h"
extern int reclen;
long recloc;
s_rsue(a) cilist *a;
{
        int n;
        if(!init) f_init();
        if(n=c_sue(a,READ)) return(n);
        reading=1;
        recpos=0;
        if(curunit->uwrt) nowreading(curunit);
        if(fread(&reclen,sizeof(int),1,cf)
                != 1)
        {       if(feof(cf))
                {       curunit->uend = 1;
                        err(a->ciend, EOF, "start");
                }
                clearerr(cf);
                err(a->cierr, errno, "start");
        }
        return(0);
}
s_wsue(a) cilist *a;
{
        int n;
        if(!init) f_init();
        if(n=c_sue(a,WRITE)) return(n);
        reading=0;
        reclen=0;
        if(!curunit->uwrt) nowwriting(curunit);
        recloc=ftell(cf);
        fseek(cf,(long)sizeof(int),1);
        return(0);
}
c_sue(a,flag) cilist *a;
{
        if(a->ciunit >= MXUNIT || a->ciunit < 0)
                err(a->cierr,101,"startio");
        external=sequential=1;
        formatted=0;
        curunit = &units[a->ciunit];
        elist=a;
        if(curunit->ufd==NULL && fk_open(flag,SEQ,UNF,a->ciunit))
                err(a->cierr,114,"sue");
        cf=curunit->ufd;
        if(curunit->ufmt) err(a->cierr,103,"sue")
        if(!curunit->useek) err(a->cierr,103,"sue")
        return(0);
}
e_wsue()
{       long loc;
        fwrite(&reclen,sizeof(int),1,cf);
        loc=ftell(cf);
        fseek(cf,recloc,0);
        fwrite(&reclen,sizeof(int),1,cf);
        fseek(cf,loc,0);
        return(0);
}
e_rsue()
{
        fseek(cf,(long)(reclen-recpos+sizeof(int)),1);
        return(0);
}