Coding guideline

Markdown formatting

• Files must be encoded in UTF-8 and do not have executable permission.

• Page headers should be indented with hashes (#) rather than equal signs (=).

• Bullet lists should be indented with hyphens (-).

• Characters that are special for Markdown must be escaped. Example: \*.

• Use inline code formatting for file names unless they are links.

• All code blocks should be enclosed in backticks, with language specified.

• Use spaces for indentation to keep documents readable in plain text format.

Script formatting

• File must be encoded in UTF-8.

• Package scripts build.sh and *.subpackage.sh should not have executable permission.

• Use tabs for indentation in Shell scripts.

• Use spaces for indentation in Python scripts.

• Parenthesis of functions should not be preceded with a space.

• Avoid trailing spaces and tabs.

• Lines shouldn't be longer than 80 characters.

• Comments should be reasonable, compact and attached to a place they refer to. Do not indent them if not necessary.

• Banner comments in build.sh or *.subpackage.sh are not allowed.

Shell script coding practices

General

• Dollar parentheses $() rather than backticks `` should be employed in command substitution.

Build script (build.sh)

• Usage of sudo or su in build scripts is disallowed.

• Global scope variables must be defined in termux_step_pre_configure() function unless they are part of package metadata.

• Local (step-specific) variables must be defined with keyword local. If variable does not have such keyword, it automatically becomes visible outside of function where it was defined.

• Do not export variables if not necessary.

• Utility install is preferred over cp as the file installation program.

• Do not hardcode version numbers. Instead, use the $TERMUX_PKG_VERSION and $TERMUX_PKG_REVISION variables.

• Do not hardcode Termux prefix directory. Instead, use the $TERMUX_PREFIX variable.

• Do not hardcode Termux home directory. Instead, use the $TERMUX_ANDROID_HOME variable.

Patches

• Files must be in format usable by GNU patch utility and do not have executable permission.

• Do not hardcode Termux prefix directory. Use @TERMUX_PREFIX@ instead.

• Do not hardcode Termux home directory. Use @TERMUX_HOME@ instead.

• Highly recommended to document changes unless they are just FHS path replacements.

See also: https://github.com/termux/termux-packages/blob/master/CONTRIBUTING.md#creating-patch-files