", $tex); $tex = trim($tex); $texmd5=md5($tex); $tex_filename = "$ImgCacheDir/$texmd5.tex"; if (! file_exists($tex_filename)) { $tex_file = fopen($tex_filename,"wb"); fputs( $tex_file, $tex); } return ""; if (!file_exists("$ImgCacheDir/$texmd5.gif") && system("$MathtexCmd -f $tex_filename -o $ImgCacheDir/$texmd5") === false) return "mathtex-failed: $tex"; return "$ImgCacheUrl/$texmd5.gif"; }