assembly gcc on Mac question.

chrislee8

Registered
Code:
.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
 
could it just be that it's not in your path? Does it work if you explicitly say ./helloworld ?
 
You might have to do chmod +x helloworld to make it executable, but I think gcc will do that for you.

Then you'll have to do the ./helloworld to run it.
 
Just for reference putting . in your path like you did above is a security risk. A common account hijack is to write a program called something like "cd" which squirrels away the access privileges of someone who executes it and the does the cd. Now this is obviously only really a problem on multiuser systems but it is a good habit to get into of typing ./foo to execute foo in the current directory and not sticking . in your path.
 
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