The shell will read /ini/shell.sh during initialization to setup its
configuration.
The main commands have a long name, a one-letter alias, and may have additional common aliases.
Alias command:
> alias d delete
Delete file:
> d a.txt
> delete a.txt
Copy file:
> c a.txt b.txt
> copy a.txt b.txt
Move file:
> m a.txt b.txt
> move a.txt b.txt
Print string:
> p "Hi"
> print "Hi"
Read file:
> r a.txt
> read a.txt
Write file:
> w a.txt
> write a.txt
Write dir:
> write /usr/alice/ # with a trailing slash to create a dir instead of a file
List files in dir:
> list /usr/alice
When executed without arguments, this command will list the files of the current directory.
Goto dir:
> goto /usr/alice
When executed without arguments, this command will print the current directory.
And combiner:
> read foo.txt and read bar.txt
Or combiners:
> read foo.txt or read bar.txt
A thin arrow -> can be used for piping the output from one command to the
input of another command (TODO):
> read foo.txt -> write bar.txt
A fat arrow => can be used for redirecting directly to a file:
> read foo.txt => bar.txt
In the following example the standard output is redirected to the null device file while the standard error is kept:
> time read foo.txt => /dev/null
The standard output is implied as the source of a redirection, but it is possible to explicitly redirect a handle to another (TODO):
> time read foo.txt [1]=>[3]
Or to redirect a handle to a file:
> time read foo.txt [1]=> bar.txt
Or to pipe a handle to another command:
> time read foo.txt [1]-> write bar.txt
It is possible to chain multiple redirections:
> time read foo.txt [1]=> bar.txt [2]=> time.txt
When the arrow point to the other direction the source and destination are swapped and the standard input is implied:
> http <= req.txt => res.txt
Here we redirect req.txt to stdin and stdout to res.txt. If both files
are the same we can use this shortcut:
> http <=> tmp.txt
Redirections should be declared before piping (TODO):
> write <= req.txt => /net/http/moros.cc -> find --line href -> sort
NOTE: The following handles are available when a process is created:
stdin(0)stdout(1)stderr(2)stdnull(3)
A redirection with a single arrow head will truncate its destination while
multiple heads like =>> will append to it.
NOTE: Arrows can be longer, and also shorter in the case of fat arrows:
> read foo.txt --> write bar.txt
> read foo.txt -> write bar.txt
> read foo.txt ==> bar.txt
> read foo.txt => bar.txt
> read foo.txt > bar.txt
> write bar.txt <== foo.txt
> write bar.txt <= foo.txt
> write bar.txt < foo.txt
> read foo.txt ==>> bar.txt
> read foo.txt =>> bar.txt
> read foo.txt >> bar.txt
- Name of the shell or the script:
$0 - Script arguments:
$1,$2,$3,$4, ... - Exit code:
$? - Process environment variable:
$HOME, ... - Shell environment variable:
$foo, ...
Setting a variable in the shell environment is done with the following command:
> set foo 42
> set bar "Alice and Bob"
And accessing a variable is done with the $ operator:
> print $foo
42
> print "Hello $bar"
Hello Alice and Bob
The process environment is copied to the shell environment when a session is started. By convention a process env var should be in uppercase and a shell env var should be lowercase.
Unsetting a variable is done like this:
> unset foo
MOROS Shell support filename expansion or globbing for * and ? wildcard
characters, where a pattern given in an argument of a command will be replaced
by files matching the pattern.
*means zero or more chars except/?means any char except/
For example /tmp/*.txt will match any files with the txt extension inside
/tmp, and a?c.txt will match a file named abc.txt.
The tilde character ~ is a shortcut to $HOME so ~/test will be expanded
to $HOME/test by the shell.