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# Read a character from stdin, save it to a global, write it to stdout.
#
# To run:
# $ ./translate_subx 000init.subx apps/ex4.subx
# $ ./a.elf
== data
# the global variable we save to
X:
0/imm32 # space for read() to write to
== code
Entry:
# read(stdin, X, 1)
# . fd = 0 (stdin)
bb/copy-to-ebx 0/imm32
# . data = X (location to write result to)
b9/copy-to-ecx X/imm32
# . size = 1 character
ba/copy-to-edx 1/imm32
# . syscall
e8/call syscall_read/disp32
# write(stdout, X, 1)
# . fd = 1 (stdout)
bb/copy-to-ebx 1/imm32
# . initialize X (location to read from)
b9/copy-to-ecx X/imm32
# . size = 1 character
ba/copy-to-edx 1/imm32
# . syscall
e8/call syscall_write/disp32
# exit(ebx)
e8/call syscall_exit/disp32
# . . vim:nowrap:textwidth=0
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