file->chmod

Changes file permissions.

Target member

Signature

1file->chmod(to::integer)

Changes file permissions.

file->chmod is called with member syntax on a receiver value. file->chmod touches paths or filesystem data. Resolve paths deliberately and avoid mixing visitor-provided path fragments with trusted server paths without validation.

Parameters

to: Required value of type integer. Supply to positionally unless the signature shows a keyword form.

In web-serving modes, request-targeted application file access cannot escape the configured document_root. That boundary can come from the .ini file, the --docroot flag used by the LaiRu HTTP server or FPM process, or FastCGI values such as DOCUMENT_ROOT and SCRIPT_FILENAME supplied by nginx or Apache. See the web root directory, FastCGI options, and LaiRu FPM pages for the deployment side of that boundary.

Examples

Basic call

1file('/tmp/a.txt')->chmod(420)

The example assumes a trusted path. Validate or resolve any path built from visitor input.

Guard a write operation under an application directory

1[2local(base) = '/var/www/html/uploads'3local(name) = string(web_request->param('name'))->trim45if(#name->contains('/') || #name->contains('..')) => {6    fail('Bad filename')7}89local(src) = file(#base + '/incoming/' + #name)10local(dst) = #base + '/published/' + #name11if(#src->exists) => {12    #src->moveTo(#dst, true)13}14]

Before moving, copying, deleting, or changing permissions, reduce visitor input to a filename or another narrow value you can validate.