1 files changed, 104 insertions, 0 deletions
diff --git a/reference/C/CONTRIB/SNIP/addhndls.c b/reference/C/CONTRIB/SNIP/addhndls.c
new file mode 100755
index 0000000..892e550
--- /dev/null
+++ b/reference/C/CONTRIB/SNIP/addhndls.c
@@ -0,0 +1,104 @@
+/*
+**  ADDHNDLS.C
+**
+**  A compilation of public domain sources originally written by
+**  Doug Burger and Bob Jarvis
+**
+**  Collected and modified for Zortech, Microsoft, and Borland by Bob Stout
+**
+**  Demonstrates relocating the file handle table under DOS 3.x
+**  for having more than the usual 20 files open in a single
+**  program
+*/
+
+#include <stdio.h>
+#include <dos.h>
+#include <io.h>
+#include <fcntl.h>
+
+#define TABLE_SIZE 255        /* NOTE: *Must* be <= FILES in CONFIG.SYS */
+
+#ifdef TEST
+ #if !defined(__ZTC__) && !defined(__TURBOC__)  /* i.e. #if MSC/QC      */
+  #include <stdlib.h>
+  #define MK_FP(seg,offset) \
+         ((void far *)(((unsigned long)(seg)<<16) | (unsigned)(offset)))
+
+  /* MSC's open() is funny - this code only works with _dos_open()      */
+
+  int open(const char *name, int mode, ...)
+  {
+          int hdl;
+
+          if (0 == _dos_open(name, mode, &hdl))
+                  return hdl;
+          else    return -1;
+  }
+ #endif /* MSC */
+#endif /* TEST */
+
+unsigned char handle_table[TABLE_SIZE];     /* table of file DOS handles    */
+unsigned char far * far * handle_ptr;       /* ptr to DOS's ptr to hand.    */
+unsigned int far *handle_count;             /* ptr to handle count          */
+
+int relocate(void)
+{
+    switch (_osmajor)
+    {
+    case 2:
+        return -1;
+    case 3:
+        if (3 > _osminor)
+        {                                       /* by Doug Burger           */
+            unsigned int i;
+
+            handle_count = MK_FP(_psp, 0x32);   /* handle count at PSP:32h  */
+            handle_ptr = MK_FP(_psp, 0x34);     /* table ptr at PSP:34h     */
+            for (i = 0; i < *handle_count; i++) /* relocate exiting table   */
+                handle_table[i] = (*handle_ptr)[i];
+            for (i = *handle_count; i < TABLE_SIZE; i++)    /* init. rest   */
+                handle_table[i] = 255;
+            *handle_ptr = handle_table;         /* set pointer to new table */
+            *handle_count = TABLE_SIZE;         /* set new table size       */
+            return 0;
+        }
+        else
+    default:                                    /* DOS 4+                   */
+        {                                       /* by Bob Jarvis            */
+            union REGS regs;
+
+            regs.h.ah = 0x67;
+            regs.x.bx = TABLE_SIZE | 1;         /* has to be an odd number  */
+
+            intdos(&regs, &regs);
+
+            if(regs.x.cflag)                    /* error                    */
+                return -1;
+            else
+                return 0;
+        }
+    }
+}   /*  relocate()  */
+
+/*
+**  Test code
+*/
+
+#ifdef TEST
+
+void main(void)
+{
+    int c, h;
+
+    relocate();
+
+    c = 0;
+    while ((h = open("CON", O_RDONLY)) >= 0)        /* DOS closes files */
+    {
+        c++;                                        /* on exit, so I    */
+        printf("handle = %d\n", h);                 /* don't bother     */
+    }                                               /* saving handles   */
+    printf("total opened files = %d\n", c);
+}   /*  ADDHNDLS.C  */
+
+#endif /* TEST */