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chrislee8
Aug 5, 2004, 02:32 PM
.data ; section declaration - variables only

msg:
.ascii "Hello, world!\n\0"
len = . - msg ; length of our dear string

.text ; section declaration - begin code

.globl _main
_main:

# write our string to stdout

li r0, 4 ; syscall number (sys_write)
li r3, 1 ; first argument: file descriptor (stdout)
; second argument: pointer to message to write
lis r4, ha16(msg); load top 16 bits of &msg
addi r4, r4,lo16(msg) ; load bottom 16 bits
li r5, len ; third argument: message length
sc ; call kernel

# and exit

li r0, 1 ; syscall number (sys_exit)
li r3, 1 ; first argument: exit code
sc ; call kernel



this is the assembly code, then I do this at the root prompt:
gcc helloworld.s -o helloworld, it compiles and create the helloworld, i thought the will be executable to run, so I run it, it says helloworld command not found.

so what the process of having the executable to run and display 'hello world' as my program does?

thanks

Santiago
Aug 5, 2004, 03:24 PM
By default, the current directory is not in your path; the file is being created, but the command line doesn't know to look for it there. Under bash, use:

export PATH=${PATH}:.

Under tcsh, I think it would be: setenv PATH ${PATH}:.

If you need to run programs from the current working directory on a regular basis, you should add this line to your shell config files.

chrislee8
Aug 5, 2004, 03:37 PM
thanks man
it works