MOROS Shell

Configuration

The shell will read /ini/shell.sh during initialization to setup its configuration.

Commands

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.

Combiners (TODO)

And combiner:

> read foo.txt and read bar.txt

Or combiners:

> read foo.txt or read bar.txt

Pipes and Redirections (WIP)

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

Variables

• Name of the shell or the script: $0
• Script arguments: $1, $2, $3, $4, ...
• Exit code: $?
• Environment variable: $HOME, ...
• Shell variable: $foo, ...

Setting a variable in the shell 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

Unsetting a variable is done like this:

> unset foo

Environment variables are copied to the shell when a session is started. By convention an env var should be in uppercase and a shell var should be lowercase. They can be changed by using --env or -e.

> date
2026-04-21 17:24:06 +0000

> set --env TZ 7200

> date
2026-04-21 19:24:14 +0200

Globbing

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.

Tilde Expansion

The tilde character ~ is a shortcut to $HOME so ~/test will be expanded to $HOME/test by the shell.