Category : C++ Source Code
Archive   : C_ALL.ZIP
Filename : TI1030.ASC

PRODUCT : Borland C++ NUMBER : 1030
VERSION : 3.x
OS : DOS
DATE : November 11, 1992 PAGE : 1/4

TITLE : Using XFCBs to set/remove Volume Labels







/* ------------------ [ SET VOLUME LABEL ] ----------------- *\
| Finding the volume label of a particular Media can be |
| achieved with the findfirst() function of the Borland C/C++ |
| compilers. Modifying the Volume Label, however, requires |
| using Extended File Control Blocks. The following function |
| ( and Macros ) can be used to Set and Remove Volume Labels. |
\* --------------------------------------------------------- */


#include
#include


#pragma option -a-
struct EXTENDEDFCB
{
char extSignature ;
char extReserved1[5] ;
char extAttribute ;
char extDriveID ;
char extFileName[8] ;
char extExtent[3] ;
short extCurBlockNo ;
short extRecSize ;
char extFileSize[4] ;
short extFileDate ;
short extFileTime ;
char extReserved2[8] ;
char extCurRecNo ;
char extRandonRecNo[4];
};
#pragma option -a.




/* -------------------- [ FCB MACROS ]----------------------- *\
| The following MACROS take advantage of Borland C++'s |
| pseudoregisters and the __emit__() function to create a |
| wrapper around INT 21, FUNCTIONS 13H and 16H which allow for |













PRODUCT : Borland C++ NUMBER : 1030
VERSION : 3.x
OS : DOS
DATE : November 11, 1992 PAGE : 2/4

TITLE : Using XFCBs to set/remove Volume Labels.




| the deletion and creation of FILES using FCBS. The MACRO can|
| be passed either an FCB or and Extended FCB structure with |
| the various fields already initialized. The result of the |
| operation is kept in the AL register... |
\* ---------------------------------------------------------- */
#define CreateFCB( xfcb ) __emit__( 0x1E ); /* PUSH DS */\
_AH = 0x2F; /* Get Current DTA */\
geninterrupt( 0x21 ); /* Call Upon DOS.. */\
__emit__( 0x06, 0x53 ); /* PUSH ES - PUSH BX */\
_DS = FP_SEG( &xfcb ); /* Load Seg. of New DTA */\
_DX = FP_OFF( &xfcb ); /* Load Off. of New DTA */\
_AH = 0x1A; /* Set DTA Function.. */\
geninterrupt( 0x21 ); /* Call Upon DOS */\
_AH = 0x16; /* Create File Function */\
geninterrupt( 0x21 ); /* Call Upon DOS */\
__emit__( 0x5A, 0x1F ); /* POP DX - POP DS */\
__emit__( 0x50 ); /* PUSH AX ( results ) */\
_AH = 0x1A; /* Set ( Restore ) DTA */\
geninterrupt( 0x21 ); /* Call Upon DOS */\
__emit__( 0x58 ); /* Restore Results... */\
__emit__( 0x1F ); /* Restore DS value... */

#define DeleteFCB( xfcb ) __emit__( 0x1E ); /* PUSH DS */\
_AH = 0x2F; /* Get Current DTA */\
geninterrupt( 0x21 ); /* Call Upon DOS.. */\
__emit__( 0x06, 0x53 ); /* PUSH ES - PUSH BX */\
_DS = FP_SEG( &xfcb ); /* Load Seg. of New DTA */\
_DX = FP_OFF( &xfcb ); /* Load Off. of New DTA */\
_AH = 0x1A; /* Set DTA Function.. */\
geninterrupt( 0x21 ); /* Call Upon DOS */\
_AH = 0x13; /* Delete File Function */\
geninterrupt( 0x21 ); /* Call Upon DOS */\
__emit__( 0x5A, 0x1F ); /* POP DX - POP DS */\
__emit__( 0x50 ); /* PUSH AX ( results ) */\
_AH = 0x1A; /* Set ( Restore ) DTA */\
geninterrupt( 0x21 ); /* Call Upon DOS */\
__emit__( 0x58 ); /* Restore Results... */\
__emit__( 0x1F ); /* Restore DS value... */




/* --------------- [ SET VOLUME LABEL ]--------------------- *\













PRODUCT : Borland C++ NUMBER : 1030
VERSION : 3.x
OS : DOS
DATE : November 11, 1992 PAGE : 3/4

TITLE : Using XFCBs to set/remove Volume Labels.




| This function modifies the VOLUME LABEL of the specified |
| Drive using extended FCBs. The parameters are as follows: |
| driveNum: 0 for current, 1 for A:, 2 for B:, 3 for C: etc|
| Label : ASCIIZ string containing new label ( If NULL |
| current label is merely removed ). |
| RETURNS : 0x00-Successful 0xFF-Failed |
\* --------------------------------------------------------- */
int SetVolLabel( int driveNum, char *Label )
{
char *p;
struct EXTENDEDFCB xfcb;

memset(( void * )&xfcb, 0x20, sizeof( xfcb ));

xfcb.extSignature = 0xFF; /* Signal Extended FCB */
xfcb.extAttribute = 0x08; /* Volume's Attribute */
xfcb.extDriveID = ( char )driveNum; /* Drive ID.*/

memset(( void * )xfcb.extFileName, '?', 11 );
DeleteFCB( xfcb ); /* Delete any LABEL */

if ( !Label ) /* NULL Label ? */
return(( int )_AL ); /* Just return if YES..*/

memset(( void * )xfcb.extFileName, ' ', 11 );
for( p = xfcb.extFileName;
p < ( char * )&xfcb.extCurBlockNo;
p++ )
{
if ( *Label == NULL )
break;
*p = *Label++;
}
CreateFCB( xfcb ); /* Create New Label.. */
return(( int )_AL ); /* Return Results.. */
}




int main( int argc, char *argv[] )
{
if ( argc > 1 )













PRODUCT : Borland C++ NUMBER : 1030
VERSION : 3.x
OS : DOS
DATE : November 11, 1992 PAGE : 4/4

TITLE : Using XFCBs to set/remove Volume Labels.




SetVolLabel( 0, argv[1] ); /* Set Label of Local */
else
SetVolLabel( 0, NULL ); /* Clear Label of Local*/
return( 0 );
}