Builtin Commands

and

COMMAND; and COMMAND

Execute the command if the shell's previous status is success

bg

bg [PID]

Resumes a stopped background process. If no process is specified, the previous job will resume.

calc

calc [EXPRESSION]

Calculate a mathematical expression. If no expression is given, it will open an interactive expression engine. Type exit to leave the engine.

cd

cd [PATH]

Change the current directory and push it to the stack. Omit the directory to change to home

contains

contains KEY [VALUE...]

Evaluates if the supplied argument contains a given string

disown

disown [-r | -h | -a ][PID...]

Disowning a process removes that process from the shell's background process table. If no process is specified, the most recently-used job is removed

drop

drop VARIABLE
drop -a ARRAY_VARIABLE

Drops a variable from the shell's variable map. By default, this will drop string variables from the string variable map. If the -a flag is specified, array variables will be dropped from the array variable map instead.

echo

echo [ -h | --help ] [-e] [-n] [-s] [STRING]...

Display a line of text

Options

-e: enable the interpretation of backslash escapes
-n: do not output the trailing newline
-s: do not separate arguments with spaces

Escape Sequences

When the -e argument is used, the following sequences will be interpreted:

\: backslash
\a: alert (BEL)
\b: backspace (BS)
\c: produce no further output
\e: escape (ESC)
\f: form feed (FF)
\n: new line
\r: carriage return
\t: horizontal tab (HT)
\v: vertical tab (VT)

ends-with

ends-with KEY [VALUE...]

Evaluates if the supplied argument ends with a given string

eq

eq [ -h | --help ] [not]

Returns 0 if the two arguments are equal

eval

eval COMMAND

evaluates the evaluated expression

exists

exists [-a ARRAY] [-b BINARY] [-d PATH] [--fn FUNCTION] [[-s] STRING]

Performs tests on files and text

exec

exec [-ch] [--help] [command [arguments ...]]

Execute a command, replacing the shell with the specified program. The arguments following the command become the arguments to the command.

options

-a ARRAY: array var is not empty
-b BINARY: binary is in PATH
-d PATH: path is a directory
-f PATH: path is a file
--fn FUNCTION: function is defined
-s STRING: string var is not empty
STRING: string is not empty

exit

exit

Exits the current session and kills all background tasks

false

false

Do nothing, unsuccessfully

fg

fg [PID]

Resumes and sets a background process as the active process. If no process is specified, the previous job will be the active process.

fn

fn

Print list of functions

help

help COMMAND

Display helpful information about a given command or list commands if none specified

history

history

Display a log of all commands previously executed

ion_docs

ion_docs

Opens the Ion manual

jobs

jobs

Displays all jobs that are attached to the background

matches

matches VARIABLE REGEX

Checks if a string matches a given regex

not

not COMMAND

Reverses the exit status value of the given command.

or

COMMAND; or COMMAND

Execute the command if the shell's previous status is failure

popd

popd

Pop a directory from the stack and returns to the previous directory

pushd

pushd DIRECTORY

Push a directory to the stack.

random

random
random SEED
random START END
random START STEP END
random choice [ITEMS...]

RANDOM generates a pseudo-random integer from a uniform distribution. The range (inclusive) is dependent on the arguments passed. No arguments indicate a range of [0; 32767]. If one argument is specified, the internal engine will be seeded with the argument for future invocations of RANDOM and no output will be produced. Two arguments indicate a range of [START; END]. Three arguments indicate a range of [START; END] with a spacing of STEP between possible outputs. RANDOM choice will select one random item from the succeeding arguments.

Due to limitations in the rand crate, seeding is not yet implemented

read

read VARIABLE

Read some variables

set

set [ --help ] [-e | +e] [- | --] [STRING]...

Set or unset values of shell options and positional parameters. Shell options may be set using the '-' character, and unset using the '+' character.

OPTIONS

e: Exit immediately if a command exits with a non-zero status.
--: Following arguments will be set as positional arguments in the shell.
- If no argument are supplied, arguments will be unset.
-: Following arguments will be set as positional arguments in the shell.
- If no arguments are suppled, arguments will not be unset.

source

source [PATH]

Evaluate the file following the command or re-initialize the init file

starts-with

ends-with KEY [VALUE...]

Evaluates if the supplied argument starts with a given string

suspend

suspend

Suspends the shell with a SIGTSTOP signal

test

test [EXPRESSION]

Performs tests on files and text

Options

-n STRING: the length of STRING is nonzero
STRING: equivalent to -n STRING
-z STRING: the length of STRING is zero
STRING = STRING: the strings are equivalent
STRING != STRING: the strings are not equal
INTEGER -eq INTEGER: the integers are equal
INTEGER -ge INTEGER: the first INTEGER is greater than or equal to the first INTEGER
INTEGER -gt INTEGER: the first INTEGER is greater than the first INTEGER
INTEGER -le INTEGER: the first INTEGER is less than or equal to the first INTEGER
INTEGER -lt INTEGER: the first INTEGER is less than the first INTEGER
INTEGER -ne INTEGER: the first INTEGER is not equal to the first INTEGER
FILE -ef FILE: both files have the same device and inode numbers
FILE -nt FILE: the first FILE is newer than the second FILE
FILE -ot FILE: the first file is older than the second FILE
-b FILE: FILE exists and is a block device
-c FILE: FILE exists and is a character device
-d FILE: FILE exists and is a directory
-e FILE: FILE exists
-f FILE: FILE exists and is a regular file
-h FILE: FILE exists and is a symbolic link (same as -L)
-L FILE: FILE exists and is a symbolic link (same as -h)
-r FILE: FILE exists and read permission is granted
-s FILE: FILE exists and has a file size greater than zero
-S FILE: FILE exists and is a socket
-w FILE: FILE exists and write permission is granted
-x FILE: FILE exists and execute (or search) permission is granted