wp-admin/includes/class-wp-filesystem-ftpext.php:183Reads entire file into a string.
$filestringstring|false public function get_contents( $file ) { if ( ! $this->link ) { return false; } $tempfile = wp_tempnam( $file ); $temphandle = fopen( $tempfile, 'w+' ); if ( ! $temphandle ) { unlink( $tempfile ); return false; } if ( ! ftp_fget( $this->link, $temphandle, $file, FTP_BINARY ) ) { fclose( $temphandle ); unlink( $tempfile ); return false; } fseek( $temphandle, 0 ); // Skip back to the start of the file being written to. $contents = ''; while ( ! feof( $temphandle ) ) { $contents .= fread( $temphandle, 8 * KB_IN_BYTES ); } fclose( $temphandle ); unlink( $tempfile ); return $contents; }Introduced in 2.5.0. Unchanged from 6.7.7 through 7.1.0.
Signature, return type and hooks compared across 5 parsed releases.
src/wp-admin/includes/class-wp-filesystem-ftpext.php, and regenerated for each WordPress release so it tracks the code rather than a snapshot of it.