Execution of shell commands.
color_default
controls whether color will actually do coloring.
show msg
outputs the message msg
on stdout.
warn msg
outputs the warning message msg
on stderr.
error msg
outputs the error message msg
on stderr.
fatal_error i msg
output the error message msg
on stderr
and stops the program with exit code i
.
verbose_default
defines the default value for the ?verbose
argument
of this module.
has_cmd cmd
is true
iff the shell has the command cmd
.
Execute a shell command.
Execute a shell command and returns its output.
Execute a command in a given directory.