To run a quick sanity check on a PHP script, run:
php -l filename
EXAMPLE:
Warning at line 46, character 15: net-enabling start-tag; possibly missing required quotes around an attribute value or using XHTML syntax in HTML
Error at line 61, character 61: text is not allowed here; try wrapping the text in a more descriptive container
Error at line 61, character 93: end tag for element “OPTION” which is not open; try removing the end tag or check for improper nesting of elements
Error at line 64, character 18: missing a required sub-element of “SELECT”
Error at line 69, character 30: required attribute “TYPE” not specified
Error at line 69, character 30: element “SCRIPT” not allowed here; check which elements this element may be contained within