simple read char app return wrong value?

Hi group!

so i decided to go with nasm and linux. after reading some portion of PGU i decided to write an app to read a character from keyboard and exit. so here is the code:

; readc.asm - read a character from standard input and exit.
section .text

global _start

_start:
mov ebx, 0h ; standard input
mov ecx, buf ; input array
mov edx, 01h ; 1 character to read
mov eax, 03h ; syatem call number for read
int 080h

mov ebx, eax ; byte read
mov eax, 01h ; syatem call number for exit
int 080h

section .bss

buf resb 01h ; array for input

is everything correct here?
but when i run this everything is okay when i enter single character or i press crtl-d for end of file, but when i enter several characters after my app exits bash somehow reads them and complains. here is some examples.

1.
# ./readc
c
#
#

2.
# ./readc
ctrl-d
#

3.
# ./readc
skjalskj
# kjalskj
bash: kjalskj: command not found
#

what is happened here? how can avoid input to readc from being read by bash? also the exit code for example 1 is 1 and for example 2 is 0 but for example 3 it is 127. does anyone know what 127 means? 1 and 0 seem to be correct as said in man 2 read.


also Duntemann's book mentions setting up "stack frame". is that only for c library or do i have to do that for above program also?

thanks to all.
.

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