Write CLOB XML output to a file on UNIX box (file size 32 K)

Question

All,
Can someone give me a sample code of how to write a CLOB output in a CLOB variable (holds XML output generated from DBMS_XMLQUERY) to a text file on UNIX box?
I found on ask tom a technique which only write upto 32K length. My CLOB output is more than 32K.
from ASK TOM:
create or replace
procedure clob_to_file( p_dir in varchar2,
p_file in varchar2,
p_clob in clob )
as
l_output utl_file.file_type;
l_amt number default 32000;
l_offset number default 1;
l_length number default
nvl(dbms_lob.getlength(p_clob),0);
BEGIN
l_output := utl_file.fopen(p_dir, p_file, 'w', 32760);
while ( l_offset < l_length )
loop
utl_file.put(l_output,
dbms_lob.substr(p_clob,l_amt,l_offset) );
utl_file.fflush(l_output);
l_offset := l_offset + l_amt;
end loop;
utl_file.new_line(l_output);
utl_file.fclose(l_output);
end;
Thanks

Answer 1

Fortran and C strings are different. When passing a string to Fortran from C, you have to know the Fortran string's length, and pad the trailing part of the string with blanks (spaces). Modern C functions never write a string without a NUL terminator, so you cannot write directly to the Fortran string unless you ensure there is at least one extra character. My guess is that your output strings contain embedded NUL characters, which somehow causes problems in the file I/O routines, but not to stdout.
According to your C fread() calls, I am assuming that you use hard-wired lengths of len(nis)==15 and len(sys)==32.Here is an example that may work, (without the #includes). It is similar to yours, but blanks-pads the result starting from the first control or NUL character. It is also a subroutine (void result) because 'bit' was just returned uninitialized in your code. Like yours, there is no error checking, but NIS should end up all blanks if there is an error.
#define NIS_LEN 15
void operating_sys(char nis[NIS_LEN]) {
  int i;
  FILE *stream;
  nis[0]=0;
  stream=popen("/bin/nisdomainname","r");
  fgets(string,sizeof(string),stream);
  fread(nis,1,NIS_LEN,stream);
  pclose(stream);
  for (i=0;i<NIS_LEN;i++) {
    if (nis<' ') {
memset(&nis[i],' ',NIS_LEN-i);
break;