Using lupdate-pro

The lupdate-pro command line tool extracts translatable strings from qmake projects (.pro files) and updates TS files. It is specifically designed for qmake-based projects, while lupdate works with source files and JSON description files and is build-system agnostic.

Use lupdate-pro when you have a qmake project and want to extract translations based on the project structure defined in your .pro file.

lupdate-pro syntax

lupdate-pro [options] [project-file]... [-ts ts-files...]

Where:

options means one or several lupdate-pro options.
project-file is a .pro file to process.
ts-files are the TS files to generate or update.

To view the latest help, enter:

lupdate-pro -help

lupdate-pro options

Option	Action
`-help`	Display up-to-date help information and exit.
`-dump-json <file>`	Generate a JSON project description file without processing translations. This file can be passed to `lupdate` or `lrelease` using the `-project` option.
`-silent`	Do not explain what is being done.
`-pro <filename>`	Name of a .pro file. Useful for files with .pro file syntax but different file suffix. Projects are recursed into and merged.
`-pro-out <directory>`	Virtual output directory for processing subsequent .pro files.
`-pro-debug`	Trace processing .pro files. Specify twice for more verbosity.
`-ts <ts-file>...`	Specify the output TS files. This overrides `TRANSLATIONS`.
`-no-obsolete`	Drop all obsolete and vanished strings.
`-pluralonly`	Only include plural form messages.
`-no-sort`	Do not sort contexts in TS files.
`-locations {absolute\|relative\|none}`	Specify or override the way to save source code references in TS files.
`-no-ui-lines`	Do not record line numbers in references to UI files.
`-source-language <language>[_<region>]`	Specify the language of the source strings for new files.
`-target-language <language>[_<region>]`	Specify the language of the translations for new files.
`-tr-function-alias <function>{+=,=}<alias>`	Recognize `<alias>` as an alternative spelling of `<function>`.
`-version`	Display the version of `lupdate-pro` and exit.

Examples

Update translations from a qmake project

lupdate-pro myproject.pro

Generate JSON project description

Generate a JSON file describing the project structure for use with lupdate or lrelease:

lupdate-pro myproject.pro -dump-json project.json

Then use the generated JSON file with lupdate:

lupdate -project project.json

This two-step workflow is useful when you need to customize the project description or integrate with other tools.

Using lrelease Using lrelease-pro

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