exit-with 0.2.0

Exit with code, stdout & stderr
Documentation

exit-with

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Exit with code, stdout & stderr

Overview

Minimalistic command-line utility that terminates immediately after starting, while controlling the exit code, standard output (stdout) and standard error (stderr) messages, all in a single invocation.

Usage

exit-with [arg]...

All arguments are optional. Each argument can be either a literal value, or a file name. If a file name is provided, the file's contents is used as the argument value.

[!NOTE] Because of the specific usage of this utility application, the only outputs are: exit code, stdout message and stderr message. There are no additional options such as displaying version information, displaying help text, or handling invalid arguments with error messages.

How it works

The behavior of this application is defined by the following decision table:

1 2 3
i32(arg1) in true true false
arg1 in = 0 != 0 -
code out 0 arg1 0
stdout out arg2 arg3... arg1
stderr out arg3... arg2 arg2...

i32(arg1), arg1 are inputs, code, stdout, stderr are outputs. i32(x) is a function that returns true when x is a 32-bit signed integer.

There are three rules defined in columns numbered 1 to 3.

RULE 1

WHEN

  • the first argument arg1 provided to exit-with is a 32-bit signed integer

AND

  • the first argument arg1 is equal to zero

THEN

  • the returned exit code will be 0,
  • the second argument arg2 will be printed to stdout,
  • all arguments starting fromarg3... will be printed to stderr.

RULE 2

WHEN

  • the first argument arg1 provided to exit-with is a 32-bit signed integer

AND

  • the first argument arg1 is not equal to zero

THEN

  • the returned exit code will be the value of arg1,
  • all arguments starting fromarg3... will be printed to stdout (sic!),
  • the second argument arg2 will be printed to stderr (sic!).

RULE 3

WHEN

  • the first argument arg1 provided to exit-with is not a 32-bit signed integer

THEN

  • the returned exit code will be 0,
  • the first argument arg1 will be printed to stdout,
  • all arguments starting fromarg2... will be printed to stderr.

[!TIP] The destination where messages are printed out depends on the value of code.

Examples

No. arguments code stdout stderr
1 0
2 0 0
3 hello 0 hello
4 0 hello 0 hello
5 0 hello world 0 hello world
6 0 "" world 0 world
7 1 1
8 1 hello 1 hello
9 1 hello world 1 world hello
10 1 "" world 1 world

License

Licensed under either of

at your option.

Contribution

Any contributions to exit-with are greatly appreciated. All contributions intentionally submitted for inclusion in the work by you, shall be dual licensed as above, without any additional terms or conditions.