Strange Problems opening and closing IFS files

I am having problems with open and closing IFS file using Scott's IFS stuff.

I am working under 7.1 and trying to open a file on the IFS. The first time I run the program I get an Invalid Descriptor error. But if I run it again right after the first time, it works with no problem.

Then, after reading the file using the same descriptor, the close gets the same error.

Here is the code:
//------------------------------------------------------------
// Variables
//------------------------------------------------------------
d headers s 20a dim(50)
d fd s 10i 0 inz
d fdclose s 10i 0 inz
d line s 1024a
d msg s 52a
d index s 10i 0
d bytesread s 10i 0
d start s 10i 0
d len s 10i 0
d info s 256a varying
d replymsg ds likeds(ReplyMsg_T)
//------------------------------------------------------------
// Prototypes
//--------------------------------------------------------------
d lexnexrcpr pi
d pathto 256a
d path 256a
d filename 256a
/EJECT
//------------------------------------------------------------
// Main Program
//------------------------------------------------------------
/free
pathto = %trim(pathto) + x'00';
fd = open(pathto:O_RDONLY+O_TEXTDATA);
if fd < 1;
die('open ' + %trim(pathto) + %str(strerror(errno)));
*inlr = *on;
return;
endif;

// load headers
bytesread=readline(fd: %addr(line): %size(line));
if bytesread <= *zero;
sndmsg('CPF9898':'file did not have a header');
*inlr = *on;
return;
endif;
line = %trim(line) + ',';
start = 1;
for index = 1 to 50;
len = %scan(',':line:start) - start;
if len <= 0;
leave;
endif;
headers(index) = %subst(line:start:len);
headers(index) = %subst(headers(index):2);
headers(index) = %subst(headers(index):1
:%len(%trim(headers(index)))-1);
start += len + 1;
endfor;

fdclose = close(fd);
if fdclose < 1;
die('close: ' + %str(strerror(errno)));
endif;

*inlr = *on;
return;

Can you see if there is anything I am doing wrong?
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