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Simple console piping example

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Vortex:
Here is a simple console pipe example. The executable pipe.exe reads data from STDIN and converts it to uppercase.


--- Code: ---dir /b | pipe

BUILD.BAT
CRT0
FILES.TXT
PIPE.ASM
PIPE.EXE
PIPE.INC
SAMPLE.TXT
STDOUT.ASM
UPPERCASE.ASM

--- End code ---


--- Code: ---pipe "This is a test"

THIS IS A TEST
--- End code ---

Source code :


--- Code: ---include pipe.inc

BUFSIZE equ 1024

.data?

dwRead  dd ?
buffer  db BUFSIZE dup(?)

.code

main PROC C uses esi argc:DWORD,argv:DWORD

LOCAL hInput:DWORD

    invoke  GetStdHandle,STD_INPUT_HANDLE
    mov     hInput,eax

    mov     esi,OFFSET buffer
    cmp     argc,1+1
    jne     @f
    mov     edx,argv
    mov     esi,DWORD PTR [edx+4]
    call    PrintStr
    ret
@@:
    invoke  ReadFile,hInput,esi,BUFSIZE,ADDR dwRead,NULL
    test    eax,eax
    je      @f
    cmp     dwRead,0
    je      @f
    mov     eax,dwRead
    mov     BYTE PTR [esi+eax],0
    call    PrintStr
    jmp     @b
@@:
    ret

main ENDP

PrintStr PROC

    invoke  uppercase,esi
    invoke  StdOut,eax
    ret

PrintStr ENDP

END

--- End code ---

CLR:
Very nice.

CLR:
Where is @f, @b? Oh I miss the basics

TimoVJL:
From PellesC help:
Command line tools -> POASM macro assembler -> Introduction -> Special code labels:

--- Quote --- Special code labels (IA32, AMD64)
 
The special label @@ can be used anywhere to create an anonymous label. This can be useful for short jumps, since you don't need to invent a new label name. For longer jumps, it's normally better to use a more descriptive name.

To jump to the nearest preceding anonymous label, use @B (back) as the jump instructions operand. To jump to the nearest following anonymous label, use @F (forward) as the operand. Since @B and @F always reference the nearest label, there is no problem having multiple anonymous labels in the same program.

--- End quote ---

CLR:
Thank you timovjl

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