Erlang - BIFS

BIFs are functions that are built into Erlang. They usually do tasks that are impossible to program in Erlang. For example, it’s impossible to turn a list into a tuple or to find the current time and date. To perform such an operation, we call a BIF.

Let’s take an example of how BIF’s are used −

Example

-module(helloworld). 
-export([start/0]). 

start() ->   
   io:fwrite("~p~n",[tuple_to_list({1,2,3})]), 
   io:fwrite("~p~n",[time()]).

The following things need to be noted about the above example −

• In the first example, we are using the BIF called tuple_to_list to convert a tuple to a list.
• In the second BIF function, we are using the time function to output the system time.

The output of the above program will be as follows −

Output

[1,2,3]
{10,54,56}

Let’s look at some of the more BIF functions available in Erlang.

S.No	BIF Functions & Description
1	date This method returns the current system date.
2	byte_size This method returns the number of bytes contained in a Bitstring.
3	element The method returns the Nth element in the tuple.
4	float This method returns the float value of a particular number.
5	get The method returns the process dictionary as a list.
6	put This method is used to put a key,value pair in the process dictionary.
7	localtime The method is used to give the local date and time in the system.
8	memory Returns a list containing information about memory dynamically allocated by the Erlang emulator.
9	now This method returns the tuple {MegaSecs, Secs, MicroSecs} which is the elapsed time since 00:00 GMT, January 1, 1970.
10	ports Returns a list of all ports on the local node
11	processes Returns a list of process identifiers corresponding to all the processes currently existing on the local node.
12	universaltime Returns the current date and time according to Universal Time Coordinated (UTC).