[SYMBOL][A][B][C][D][E][F][G][H][I][J][K][L][M][N][O][P][Q][R][S][T][U][V][W][X][Y][Z]e-mail. [See also mail]each() functionarrays 2nd editing. [See changing]editorsaccessing avoiding for PHP code HTML Edmunds Keith elementsTITLE ellipsesImageEllipse() function ImageFilledEllipse() function else clause with if statements 2nd 3rd elseif clausewith if statements 2nd 3rd 4th email field emailChecker() function 2nd 3rd emergLogLevel directive option enablingper-directory configuration files ENCRYPT argument encryptingpasswordsuser management (file-based authentication) encryptionkeys SSL protocols end tags 2nd 3rd 4th 5th endingblock of statements 2nd ENUM data type environment modificationsinternationalization Apache, configuration changes to 2nd MySQL, configuration changes to 2nd PHP, configuration changes to 2nd environment variablesaccess control rules conditional logging CustomLog directive equal sign (=)assignment operator 2nd 3rd equivalence operator (==) identical operator (===) 2nd equivalence operator (==) errorLogLevel directive option error loglog file error messagesmysql error() function 2nd ErrorLog directiveerrorslogging errorsauthentication process 2nd 3rd logging 2nd 3rd files LogLevel directive 2nd programs syslog daemon (Unix) logsmonitoring escapeshellarg() function escapeshellcmd() function evaluatingcontrol access rules 2nd eventsrecordingerror log exclamation mark (!)not operator (!) exec() functionrunning commands with 2nd 3rd 4th existence (files)checking exit statement EXPLAIN command 2nd 3rd explode() functionbreaking strings into arrays expressionsdefined 2nd subexpressions testboolean values expressions. [See also operators]external processesoperating systemsscalability