set CY before calling 21.71 or 21.73 DOS functions (LFN, FAT32)

cmd/dir.c

@@ -291,6 +291,7 @@ static void printLFNname(char *shortName, char *ext)
     dprintf(("[LFN: path %s\n",pathbuffer)); 
 
       /* LFN get canonical LFN */
+	r.r_flags = 1;	/* CY before 21.71 calls! */
 	r.r_ax = 0x7160;
 	r.r_cx = 0x8002;
 	r.r_si = FP_OFF( pathbuffer );
@@ -760,6 +761,7 @@ static int dir_print_free(unsigned long dirs)
   displayString(TEXT_DIR_FTR_DIRS, buffer);
 
   rootname[0] = toupper(*path);
+  r.r_flags = 1;	/* CY before 21.73 calls! */
   r.r_ax = 0x7303;
   r.r_ds = FP_SEG(rootname);
   r.r_dx = FP_OFF(rootname);
@@ -770,8 +772,10 @@ static int dir_print_free(unsigned long dirs)
 
   /* Note: RBIL carry clear and al==0 also means unimplemented 
      alternately carry set and ax==undefined (usually unchanged) for unimplemented
-  */  
-  if(!( r.r_flags & 1 ) && ( r.r_ax & 0xFF) ) {
+     ecm: RBIL is wrong, CF unchanged al=0 is the typical error return.
+     EDR-DOS returns NC ax=0 so checking for al!=0 here was wrong.
+  */
+  if(!( r.r_flags & 1 ) && ( r.r_ax != 0x7300 ) ) {
 	dprintf(("[DIR: Using FAT32 info]\n"));
 	clustersize = FAT32_Free_Space.sectors_per_cluster
 	 * FAT32_Free_Space.bytes_per_sector;

lib/lfnfuncs.c

@@ -53,6 +53,7 @@ const char * getshortfilename( const char *longfilename )
     r.r_di = FP_OFF( shortfilename );
     shortfilename[0] = '\0';
     r.r_cx = 0x8001; /* Get short filename */
+    r.r_flags = 1;	/* CY before 21.71 calls! */
     r.r_ax = 0x7160;/* LFN truename function */
 
     intrpt( 0x21, &r );
@@ -82,6 +83,7 @@ static int __creat_or_truncate( const char * filename, int mode, int code )
     r.r_bx = O_WRONLY;
     r.r_cx = mode;
     r.r_dx = code;
+    r.r_flags = 1;	/* CY before 21.71 calls! */
     r.r_ax = 0x716C;
 
     intrpt( 0x21, &r );
@@ -129,6 +131,7 @@ int lfnrename( const char *oldfilename, const char *newfilename )
     r.r_dx = FP_OFF( oldfilename );
     r.r_es = FP_SEG( newfilename );
     r.r_di = FP_OFF( newfilename );
+    r.r_flags = 1;	/* CY before 21.71 calls! */
     r.r_ax = 0x7156;
 
     intrpt( 0x21, &r );
@@ -181,6 +184,7 @@ int lfnfindfirst( const char *path, struct lfnffblk *buf, unsigned attr )
     r.r_di = FP_OFF( &lfnblock );  /* LFN find block goes in ES:DI */
     r.r_si = 1;                    /* Use DOS date/time format */
     r.r_cx = attr;
+    r.r_flags = 1;	/* CY before 21.71 calls! */
     r.r_ax = 0x714E;               /* LFN Findfirst */
 
     intrpt( 0x21, &r );
@@ -226,6 +230,7 @@ int lfnfindnext( struct lfnffblk *buf )
     r.r_di = FP_OFF( &lfnblock );          /* The LFN find block */
     r.r_bx = buf->lfnax;                   /* The lfn handle set by findfirst */
     r.r_si = 1;                            /* Use DOS times */
+    r.r_flags = 1;	/* CY before 21.71 calls! */
     r.r_ax = 0x714F;
 
     intrpt( 0x21, &r );
@@ -247,6 +252,7 @@ int lfnfindclose( struct lfnffblk *buf )
     if( !buf->lfnsup || !__supportlfns ) return( 0 );
 
     r.r_bx = buf->lfnax;        /* Findfirst handle */
+    r.r_flags = 1;	/* CY before 21.71 calls! */
     r.r_ax = 0x71A1;            /* LFN findclose */
 
     intrpt( 0x21, &r );

lib/prprompt.c

@@ -140,6 +140,7 @@ void displayPrompt(const char *pr)
 
             d = getdisk();
 
+	    r.r_flags = 1;	/* CY before 21.71 calls! */
             r.r_ax = 0x7147;
             r.r_dx = 0;
             r.r_si = FP_OFF(pathname);

suppl/src/_getdcwd.c

@@ -156,6 +156,7 @@ char *_getdcwd(int drive, char Xbuf[], unsigned length)
 		r.r_dx = drive;
 		r.r_ds = FP_SEG(buf);
 #ifdef FEATURE_LONG_FILENAMES
+		r.r_flags = 1;	/* CY before 21.71 calls! */
 		r.r_ax = 0x7147;
 #else
         r.r_ax = 0x4700;

suppl/src/dfntruen.c

@@ -105,6 +105,7 @@ char *dfntruename(const char * const fnam)
 	chkHeap
 	if((h = eno_malloc(DFN_FILENAME_BUFFER_LENGTH)) != 0) {
 #ifdef FEATURE_LONG_FILENAMES
+	r.r_flags = 1;	/* CY before 21.71 calls! */
         r.r_ax = 0x7160;
         r.r_cx = 0x8002;
 #else