; -*- scheme -*-

; hello world
; print a simple string on stdout
(display "Hello World\n")

; argv
; access command line parameters (no segmentation fault accepted, nor silent exception, so some languages must explicitly check the presence of the argument)
(format #t "~A\n" (cadr command-line))

; env
; access environment variable
(format #t "~A\n" (getenv "HOME"))

; test file exists
; return exit code error (non zero) if a file does not exist
(exit (access? "/etc/mtab" F_OK))

; test file readable
; return exit code error (non zero) if a file is not readable
(exit (access? "/etc/mtab" R_OK))

; formatting
; print integers in a simple formatted string
(let ((a 1) (b 2))
  (format #t "~A + ~A = ~A\n" a b (+ a b)))


; system
; call an external program and check the return value
(if (not (= (system "false") 0)) 
  (display "false failed\n" (current-error-port)))
(system "echo done")