run_phc := proc(phcloc::string,p::list)
  description `Calls phc from within a Maple 7 session. \
The first argument is the file name of the executable version \
of phc.  The second argument is a list of polynomials. \
On return is a list of approximations to all isolated \
roots of the system defined by p.`:
  local i,sr,infile,outfile,solfile,sols:
  sr := convert(rand(),string): solfile := sols||sr:
  infile := input||sr: outfile := output||sr:
  fopen(infile,WRITE): fprintf(infile,`%d\n`,nops(p)):
  for i from 1 to nops(p) do
    fprintf(infile,`%s;\n`,convert(p[i],string)):
  end do;
  fclose(infile):
  ssystem(phcloc||` -b `||infile||` `||outfile):
  ssystem(phcloc||` -z `||outfile||` `||solfile):
  read(solfile): sols := %:
  fremove(infile): fremove(outfile): fremove(solfile):
  RETURN(sols);
end proc: