PHP函数库分类三十.doc

PHP函数库分类三十10.PHP选项/信息函数列表2 getenv- Gets the value of an environment variablegetenv(PHP 4, PHP 5)getenvGets the value of an environment variable说明stringgetenv(string$varname)Gets the value of an environment variable.You can see a list of all the environmental variables by usingphpinfo(). Many of these variables are listed withinRFC 3875, specifically section 4.1, Request Meta-Variables.参数varnameThe variable name.返回值Returns the value of the environment variablevarname, orFALSEif the environment variablevarnamedoes not exist.范例Example #1getenv()Example getlastmod- Gets time of last page modificationgetlastmod(PHP 4, PHP 5)getlastmodGets time of last page modification说明intgetlastmod(void)Gets the time of the last modification of the current page.If youre interested in getting the last modification time of a different file, consider usingfilemtime().返回值Returns the time of the last modification of the current page. The value returned is a Unix timestamp, suitable for feeding todate(). ReturnsFALSEon error.范例Example #1getlastmod()example getmyinode- Gets the inode of the current scriptgetmyinode(PHP 4, PHP 5)getmyinodeGets the inode of the current script说明intgetmyinode(void)Gets the inode of the current script.返回值Returns the current scripts inode as an integer, orFALSEon error. getopt- Gets options from the command line argument listgetopt(PHP 4 = 4.3.0, PHP 5)getoptGets options from the command line argument list说明arraygetopt(string$options,array$longopts )Parses options passed to the script.参数optionsEach character in this string will be used as option characters and matched against options passed to the script starting with a single hyphen (-).For example, an option stringxrecognizes an option-x.Only a-z, A-Z and 0-9 are allowed.longoptsAn array of options. Each element in this array will be used as option strings and matched against options passed to the script starting with two hyphens (-).For example, an longopts elementoptrecognizes an option-opt.Theoptionsparameter may contain the following elements: Individual characters (do not accept values) Characters followed by a colon (parameter requires value) Characters followed by two colons (optional value)Option values are the first argument after the string. It does not matter if a value has leading white space or not.Note:Optional values do not accept (space) as a separator.Note:The format for theoptionsandlongoptsis almost the same, the only difference is thatlongoptstakes an array of options (where each element is the option) where asoptionstakes a string (where each character is the option).返回值This function will return an array of option / argument pairs orFALSEon failure.Note:The parsing of options will end at the first non-option found, anything that follows is discarded.更新日志版本说明5.3.0Added support for = as argument/value separator.5.3.0Added support for optional values (specified with :).5.3.0Parameterlongoptsis available on all systems.5.3.0This function is no longer system dependent, and now works on Windows, too.范例Example #1getopt()exampleRunning the above script withphp script.php -fvalue -hwill output:array(2) f= string(5) value h= bool(false)Example #2getopt()example#2Running the above script withphp script.php -f value for f -v -a -required value -optional=optional value -optionwill output:array(6) f= string(11) value for f v= bool(false) a= bool(false) required= string(5) value optional= string(14) optional value option= bool(false)Example #3getopt()example#3Passing multiple options as oneRunning the above script withphp script.php -aaacwill output:array(2) a= array(3) 0= bool(false) 1= bool(false) 2= bool(false) c= bool(false) getrusage- Gets the current resource usagesgetrusage(PHP 4, PHP 5)getrusageGets the current resource usages说明arraygetrusage(int$who= 0 )This is an interface togetrusage(2). It gets data returned from the system call.参数whoIfwhois 1, getrusage will be called withRUSAGE_CHILDREN.返回值Returns an associative array containing the data returned from the system call. All entries are accessible by using their documented field names.范例Example #1getrusage()example注释Note:此函数未在 Windows 平台下实现。 get_cfg_var- Gets the value of a PHP configuration optionget_cfg_var(PHP 4, PHP 5)get_cfg_varGets the value of a PHP configuration option说明stringget_cfg_var(string$option)Gets the value of a PHP configurationoption.This function will not return configuration information set when the PHP was compiled, or read from an Apache configuration file.To check whether the system is using a configuration file, try retrieving the value of the cfg_file_path configuration setting. If this is available, a configuration file is being used.参数optionThe configuration option name.返回值Returns the current value of the PHP configuration variable specified byoption, orFALSEif an error occurs.更新日志版本说明5.3.0get_cfg_var()was fixed to be able to return array ini options. get_current_user- Gets the name of the owner of the current PHP scriptget_current_user(PHP 4, PHP 5)get_current_userGets the name of the owner of the current PHP script说明stringget_current_user(void)Returns the name of the owner of the current PHP script.返回值Returns the username as a string.范例Example #1get_current_user()example以上例程的输出类似于：Current script owner: SYSTEM get_defined_constants- Returns an associative array with the names of all the constants and their valuesget_defined_constants(PHP 4 = 4.1.0, PHP 5)get_defined_constantsReturns an associative array with the names of all the constants and their values说明arrayget_defined_constants(bool$categorize= false )Returns the names and values of all the constants currently defined. This includes those created by extensions as well as those created with thedefine() function.参数categorizeCausing this function to return a multi-dimensional array with categories in the keys of the first dimension and constants and their values in the second dimension.以上例程的输出类似于：Array( Core = Array ( E_ERROR = 1 E_WARNING = 2 E_PARSE = 4 E_NOTICE = 8 E_CORE_ERROR = 16 E_CORE_WARNING = 32 E_COMPILE_ERROR = 64 E_COMPILE_WARNING = 128 E_USER_ERROR = 256 E_USER_WARNING = 512 E_USER_NOTICE = 1024 E_ALL = 2047 TRUE = 1 ) pcre = Array ( PREG_PATTERN_ORDER = 1 PREG_SET_ORDER = 2 PREG_OFFSET_CAPTURE = 256 PREG_SPLIT_NO_EMPTY = 1 PREG_SPLIT_DELIM_CAPTURE = 2 PREG_SPLIT_OFFSET_CAPTURE = 4 PREG_GREP_INVERT = 1 ) user = Array ( MY_CONSTANT = 1 )返回值更新日志版本说明5.3.1Wind