cfunction
(os/chmod path mode)
Change file permissions, where mode is a permission string as
returned by os/perm-string, or an integer as returned by
os/perm-int. When mode is an integer, it is interpreted as a Unix
permission value, best specified in octal, like 8r666 or 8r400.
Windows will not differentiate between user, group, and other
permissions, and thus will combine all of these permissions.
Returns nil.
(spit "/tmp/hello.sh" "#!/bin/bash\necho 'Hello from Bash!'\n")
(os/chmod "/tmp/hello.sh" "rwx------")
(os/setenv "PATH" (string (os/getenv "PATH") ":/tmp"))
(os/shell "hello.sh")