Inline ASM troubles... [SOLVED]

[pcmattman]

I have finally got my OS working again

Now I'm working on the stdlib for developers, and I've already run into a problem.

I'm trying this for my putc function:

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__asm__ __volatile__ ( "movb %0,%edx" : : "d" ( c ) );
__asm__ __volatile__ ( "movd $0x1,%eax" );
__asm__ __volatile__ ( "int $0x15" );

This is the syscall my operating system supports to handle the same thing as 'putc' in kernel-space. EDX is meant to hold the character.

GCC complains with this error message:

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putc_stdlib.c:5: error: invalid 'asm': operand number missing after %-letter

Edit: fixed it:

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__asm__ __volatile__ ( "movb %0,%%dl" : : "d" ( c ) );
__asm__ __volatile__ ( "movb $0x1,%al" );
__asm__ __volatile__ ( "int $0x15" );

EDIT: 4 years later... wow
Check out the inline assembly examples for a much better way to do this kind of thing.

Also, the actual problem is in "mov %0, %dl", which should be "mov %0, %%dl" in this context.