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Simple as it gets, add this to the end:david wrote:using MASM,
The size of complied file is 3K, I want to extend file to 32K, and fill file with 0.
how to do ?
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times 32768-($-$$) db 0You're wrong, it can be DOS too.JamesM wrote:MASM - can only be windows.
The DUP Operator
You can also declare an array with the DUP operator. This operator works with any of the data allocation directives described in "Allocating Memory for Integer Variables" in Chapter 4. In the syntax
count DUP (initialvalue [[, initialvalue]]...)
the count value sets the number of times to repeat all values within the parentheses. The initialvalue can be an integer, character constant, or another DUP operator, and must always appear within parentheses. For example, the statement
barray BYTE 5 DUP (1)
allocates the integer 1 five times for a total of 5 bytes.
The following examples show various ways to allocate data elements with the DUP operator:
array DWORD 10 DUP (1) ; 10 doublewords
; initialized to 1
buffer BYTE 256 DUP (?) ; 256-byte buffer
masks BYTE 20 DUP (040h, 020h, 04h, 02h) ; 80-byte buffer
; with bit masks
three_d DWORD 5 DUP (5 DUP (5 DUP (0))) ; 125 doublewords
; initialized to 0
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ORG 510 ; Make the file 512 bytes long
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org 32767 ; 32 * 1024 - 1
db 0
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.model tiny
.code
.386
start:
xor ax, ax
org 65535 ; 64 * 1024 -1
db 0
end start
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masm test.asm
link test.obj
exe2bin test.exe test.bin
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F:\EzNet>masm test.asm
Microsoft (R) MASM Compatibility Driver
Copyright (C) Microsoft Corp 1993. All rights reserved.
Invoking: ML.EXE /I. /Zm /c /Ta test.asm
Microsoft (R) Macro Assembler Version 6.11c
Copyright (C) Microsoft Corp 1981-1994. All rights reserved.
Assembling: test.asm
F:\EzNet>link test.obj
Microsoft (R) Segmented Executable Linker Version 5.31.009 Jul 13 1992
Copyright (C) Microsoft Corp 1984-1992. All rights reserved.
Run File [test.exe]:
List File [nul.map]:
Libraries [.lib]:
Definitions File [nul.def]:
test.obj(test.asm) : warning L4020: _TEXT : code-segment size exceeds 64K-36
LINK : warning L4021: no stack segment
F:\EzNet>exe2bin test.exe test.bin
Insufficient memory
For what company are you working that enforces this assembler, and assembly in general. Especially with this kind of dated software.david wrote:But i must using MASM in my company.
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#include <stdio.h>
#define FILE_SIZE 64*1024 // 64KB
int main (char argc, char **argv)
{
FILE *in = fopen(argv[1], "rb");
FILE *out = fopen(argv[2], "wb");
if (!in || !out)
{
fprintf(stderr, "File open error!\n");
exit(1);
}
unsigned long i;
char buffer;
for (i = 0; i < FILE_SIZE; i++)
{
if (!fread(&buffer, 1, 1, in))
buffer = '\0';
fwrite(&buffer, 1, 1, out);
}
exit(0);
}
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$ gcc -o test test.c
test.c: In function ‘main’:
test.c:18: warning: incompatible implicit declaration of built-in function ‘exit’
test.c:38: warning: incompatible implicit declaration of built-in function ‘exit’
$ echo "Howay the lads" >test.in
$ ./test test.in test.out
$ cat test.out
Howay the lads
$ ls -l test.out
-rw-r--r-- 1 james james 65536 2008-05-05 10:48 test.out
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org 65534
db 0
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.model tiny
.code
.386
start:
xor ax, ax
org 1024
org 64511
db 0
org 64511Dex wrote:What does this assemble too ?If it will allow it.Code: Select all
.model tiny .code .386 start: xor ax, ax org 1024 org 64511 db 0