NAME File::Prepend::Undoable - Prepend string to a file, with undo support VERSION This document describes version 0.05 of File::Prepend::Undoable (from Perl distribution File-Prepend-Undoable), released on 2017-07-10. FUNCTIONS prepend Usage: prepend(%args) -> [status, msg, result, meta] Prepend string to a file, with undo support. On do, will trash file, copy it to original location (with the same permission and ownership as the original) and prepend the string to the beginning of file. On undo will trash the new file and untrash the original. Some notes: * Chown will not be done if we are not running as root. * Symlink is currently not permitted. * Since transaction requires the function to be idempotent, in the "check_state" phase the function will check if the string has been prepended. It will refuse to prepend the same string twice. * Take care not to use string that are too large, as the string, being a function parameter, is entered into the transaction table. Fixed state: file exists and string has been prepended to beginning of file. Fixable state: file exists and string has not been prepended to beginning of file. Unfixable state: file does not exist or path is not a regular file (directory and symlink included). This function is not exported. This function is idempotent (repeated invocations with same arguments has the same effect as single invocation). This function supports transactions. Arguments ('*' denotes required arguments): * path* => *str* The file to prepend. * string* => *any* The string to prepend to file. Special arguments: * -tx_action => *str* For more information on transaction, see Rinci::Transaction. * -tx_action_id => *str* For more information on transaction, see Rinci::Transaction. * -tx_recovery => *str* For more information on transaction, see Rinci::Transaction. * -tx_rollback => *str* For more information on transaction, see Rinci::Transaction. * -tx_v => *str* For more information on transaction, see Rinci::Transaction. Returns an enveloped result (an array). First element (status) is an integer containing HTTP status code (200 means OK, 4xx caller error, 5xx function error). Second element (msg) is a string containing error message, or 'OK' if status is 200. Third element (result) is optional, the actual result. Fourth element (meta) is called result metadata and is optional, a hash that contains extra information. Return value: (any) HOMEPAGE Please visit the project's homepage at <https://metacpan.org/release/File-Prepend-Undoable>. SOURCE Source repository is at <https://github.com/perlancar/perl-File-Prepend-Undoable>. BUGS Please report any bugs or feature requests on the bugtracker website <https://rt.cpan.org/Public/Dist/Display.html?Name=File-Prepend-Undoable > When submitting a bug or request, please include a test-file or a patch to an existing test-file that illustrates the bug or desired feature. SEE ALSO Rinci::Transaction AUTHOR perlancar <perlancar@cpan.org> COPYRIGHT AND LICENSE This software is copyright (c) 2017, 2015, 2014, 2012 by perlancar@cpan.org. This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself.