PS1 Generator

Introduction:

Shell prompts in Bash are short status lines that appear before each command and they can show who you are where you are and the time. A custom Bash PS1 prompt helps you read context at a glance and reduces typing mistakes.

You select building blocks such as username host working directory clock exit code and a prompt character and you choose colours emphasis and backgrounds so the line stays legible. This makes a clear starting point for a custom Bash PS1 prompt.

You can import an existing PS1 string and the generator maps common tokens variables and command substitutions so you can adjust them quickly. Then you preview a sample with realistic values and copy a ready string for your shell configuration.

Test on both a dark background and a light background so colour choices remain readable. Avoid overly bright combinations and keep separators simple so the eye lands on the parts you check most.

If you include the Git branch add the helper function noted below so the branch name appears only when a repository is present.

Technical Details:

Bash prompt strings are templates evaluated before each command to produce context such as identity location and time. The primary template variable is PS1 which is a sequence of text plus backslash escapes and optional command or variable expansions.

The generator composes PS1 from chosen tokens and wraps nonprinting terminal control sequences so line editing and width calculations remain correct. Colours and text attributes are applied using ANSI Select Graphic Rendition codes with a reset after each token.

Results are interpreted by reading the visible parts of the prompt as quick cues. Colour and emphasis signal boundaries such as user versus host or path versus time, while the final character clarifies command status or privilege.

Comparisons across machines are meaningful when terminals support the same colour depth and when the same tokens are used in the same order. Values like username or path vary by session and are resolved at prompt time.

$begin:math:display$\\e[38;2;0;255;0m$end:math:display$\u$begin:math:display$\\e[0m$end:math:display$ $begin:math:display$\\e[38;2;255;255;255m$end:math:display$@$begin:math:display$\\e[0m$end:math:display$ $begin:math:display$\\e[38;2;0;255;0m$end:math:display$\h$begin:math:display$\\e[0m$end:math:display$ $begin:math:display$\\e[38;2;255;255;255m$end:math:display$:$begin:math:display$\\e[0m$end:math:display$ $begin:math:display$\\e[38;2;0;128;255m$end:math:display$\w$begin:math:display$\\e[0m$end:math:display$ $

Variables and parameters

ANSI colour and attributes

• Colours use 24‑bit RGB via 38;2;r;g;b and backgrounds via 48;2;r;g;b.
• Attributes supported: bold 1, dim 2, italic 3, underline 4, blink 5, reverse 7.
• Each token resets with $begin:math:display$\\e[0m$end:math:display$ to avoid style bleed.

Date and time formatting

The custom date token supports a focused subset of \D{…} codes resolved at prompt time. Recognised codes include %F %Y %y %m %d %H %M %S %I %p %a %A %b %B.

Validation and bounds

I/O formats

Privacy & compliance

No data is transmitted or stored server‑side. Clipboard copy and file downloads run locally.

Assumptions & limitations

• Heads‑up Terminal must support 24‑bit colour for exact RGB output.
• Nonprinting wraps are added per token to keep cursor position stable.
• Command substitutions rely on your shell configuration.
• Git branch display requires the helper function below.
• Overly long prompts may wrap on narrow windows.
• Environment values are resolved by the shell at display time.
• Imported strings with unusual escapes may need manual adjustment.
• Colours are validated only for hex format, not contrast ratio.

Edge cases & error sources

• Invalid hex colour values are rejected and flagged.
• Empty custom date format yields a warning.
• Environment names must start with a letter or underscore.
• Unsupported terminals may ignore italic or blink attributes.
• Clipboard access can be blocked by browser settings.
• Very bright colours can reduce legibility on light themes.
• Excessive nesting of literals complicates readability.
• Long paths make prompts noisy without a basename token.
• Jobs count may be zero while background tasks exist in other shells.
• History and command numbers reset with fresh sessions.

Git helper snippet

parse_git_branch() { git branch --show-current 2>/dev/null | awk 'NF{print " (" $0 ")"}'; }

Step‑by‑Step Guide:

Shell prompts are composed from tokens and styles to produce a readable PS1 string.

1. Add tokens in your preferred order.
2. Pick colours and optional backgrounds for each token.
3. Toggle attributes like bold or underline as needed.
4. Set a delimiter, plus optional prefix and suffix.
5. Preview the result and copy the generated PS1.

Example. Username at host, colon, working directory, space, and a dollar sign gives a compact everyday prompt.

• Tip: keep delimiters short so the eye finds the tokens that matter.

FAQ:

Advanced Tips:

Tip Use dim attribute for separators so content stands out.

Tip Keep path short by mixing basename with full path selectively.

Tip Add a newline token when commands produce long outputs.

Tip Reserve bright colours for status or errors only.

Tip Group identity tokens together and filesystem tokens together for quick scanning.

Tip Use the same delimiter everywhere to build muscle memory.

Glossary:

PS1

Primary prompt string evaluated before each command.

ANSI SGR

Terminal codes that control colour and text attributes.

Nonprinting wrap

Brackets that hide control codes from width counts.

Environment variable

Named value like PATH resolved by the shell.

Command substitution

Runs a command and inserts its output.

Delimiter

String placed between tokens in the prompt.