BSD 3 development

[unix-history] / usr / src / cmd / lisp / fpipe.c

#include <stdio.h>
FILE *_dofpip(iodes)
int iodes;
{
       register FILE *p;

       for(p=_iob; (p->_flag&(_IOWRT|_IOREAD))!=0; p++)
               if (p >= _iob+_NFILE)
                       return(NULL);
       p->_file = iodes;
       p->_cnt = 0;
       p->_base = p->_ptr = NULL;
       return(p);
}

FILE * fpipe(info)
FILE *info[2];
{
       register FILE *p;
       int descrips[2];

       if(0 > pipe(descrips)) return( (FILE *) -1);

       if(NULL==(p = _dofpip(descrips[0]))) return( (FILE *) -1);
       p->_flag = (_IONBF|_IOREAD);
       info[0] = p;

       if(NULL==(p = _dofpip(descrips[1]))) return( (FILE *) -1);
       p->_flag = _IOWRT;
       info[1] = p;
       return((FILE *) 2); /*indicate sucess*/
}