1 files changed, 43 insertions, 0 deletions
diff --git a/reference/C/CONTRIB/SNIP/drvs.c b/reference/C/CONTRIB/SNIP/drvs.c
new file mode 100755
index 0000000..2002d8c
--- /dev/null
+++ b/reference/C/CONTRIB/SNIP/drvs.c
@@ -0,0 +1,43 @@
+/*
+**  DRVS.C - public domain by David Gersic, DeKalb, Il 1993
+**
+**  Routine checks how many valid disk drives are available on machine,
+**  both physical and logical drives.
+**
+**  Includes drive letters assigned with DOS SUBST command and network
+**  drives for Novell Netware (and probably other networks).
+**
+**  Compiled Under MSC 6 LARGE memory Model
+**  Should be compatible with other DOS compilers
+**
+*/
+
+#include <stdio.h>
+#include <dos.h>
+#include <stdlib.h>
+
+main()
+{
+      union REGS in, out;
+      int i;
+
+      /* Novell's shell TSRs allow up to 32 drive 'letters' to be created */
+
+      char drives[]={' ','a','b','c','d','e','f','g','h','i','j',
+                     'k','l','m','n','o','p','q','r','s','t','u',
+                     'v','w','x','y','z','[','\\',']','^','_','`'};
+
+      in.x.ax=0x4409;   /* IOCTL function - Check if block device remote  */
+      for(i = 1; i < 32; i++)
+      {
+            in.h.bl=(unsigned char)i;     /* 1==a:, 2==b:, etc.           */
+            intdos(&in,&out);
+            if(!out.x.cflag)        /* carry flag set on error            */
+            {                       /* bit 15 == subst, bit 12 == 'remote'*/
+                  printf("drive %c: is %s\n",
+                        drives[i],out.x.dx & 1<<15 ? "subst" :
+                        out.x.dx & 1<<12 ? "network" : "local");
+            }
+      }
+      return(0);
+}