[PHP] practical functions 10

// Convert the characters of IP address points into IP address v4 format

Int ip2long (string ip_address)
// Convert the IP v4 format address back to the IP point address string

String long2ip (int proper_address)
// Obtain the environment variable varname. If it succeeds, the variable value is returned. If it fails, false is returned.

String getenv (string varname)
// Used to set the system environment

Void putenv (string setting)
// Obtain the owner name of the current PHP script

String get_current_user (void)
// Call the user function specified by function_name

String get_cfg_var (string function_name [, mixed parrameter [, mixed...])
// Return the port (protocol) associated with the service, which must be TCP or UDP

Int getservbyname (string service, string protocol)
// Return the name of the service associated with the port (protocol), which must be TCP or UDP

String getservbyport (int port, string protocol)
// Obtain the absolute value

Mixed abs (mixed number)
// Square root

Float sqrt (float arg)
// The power of natural logarithm e

Float exp (float arg)
// Returns the circumference rate.

Double pi (void)
// Rounding

Double round (double val)
// Calculate the smallest integer greater than the specified number

Int ceil (float number)
// Calculate the value smaller than the specified maximum integer.

Int floor (float number)
// Obtain the maximum value

Mixed max (mixed arg1, mixed arg2. .. mixed argn)
// Obtain the minimum value

Mixed min (mixed arg1, mixed arg2. .. mixed argn)
// Obtain the random number

Int rand ([int min], [int max])
// Numeric Conversion

String base_convert (string number, int frombase, int tobase)
// Format the numeric string

String number_format (float number, int [decimals], string [decpoint], string [thounsands_sep])