How do I know which library file am i suppose to call?

[jimhakans]

Hello guys. This is my beginning with d C programming and i m confused abt these library functions. I actually dont understand how am i suppose to know which library file i have to call. I only know "stdio.h" but i have also come up with others like "genlib.h" but i dont know when to use them.
I hope u understand what i am saying. i would feel very glad if you'd help me. Thanks.

[sicarie]

You include libraries when you need to use their functionality. For instance, if you are using sockets, you include 'sys/socket.h'. Then you can instantiate their objects and use their methods.

All your includes go at the top of the program, and then you call the object and methods in the program as needed.

[arnaudk]

C without any libraries contains only a very limited set of functions. For example, if you want to print some output to the screen, you'll need to use the printf() function. This function becomes available only when you #include <stdio.h> as printf() is defined in the header file stdio.h. (The header files themselves are tied to libraries which differ for each operating system, but you don't need to know this so long as your C compiler is installed and working properly).

There many are other libraries which come as standard with any C compiler, math.h defines mathematical functions such as sin() cos() etc. stdlib.h defines some useful functions like atoi() which converts the character '1' to its integer value 1, the exit() function which terminates the program safely by flushing all buffers and closing all open streams, etc. There are many others, time.h for reading the clock, float.h, limits.h... The basic ones are described in most C programming books, you should familiarize yourself with the basic ones as you will need them most often. And remember, Google is your friend.

It is also possible to write your own header files in order to split your program over several files as it grows, and there are also many other seperately available header files for doing more complex things, check out the Gnu C library (GCL) and Gnu Scientific Library (GSL), for example.

[jimhakans]

C without any libraries contains only a very limited set of functions. For example, if you want to print some output to the screen, you'll need to use the printf() function. This function becomes available only when you #include <stdio.h> as printf() is defined in the header file stdio.h. (The header files themselves are tied to libraries which differ for each operating system, but you don't need to know this so long as your C compiler is installed and working properly).

There many are other libraries which come as standard with any C compiler, math.h defines mathematical functions such as sin() cos() etc. stdlib.h defines some useful functions like atoi() which converts the character '1' to its integer value 1, the exit() function which terminates the program safely by flushing all buffers and closing all open streams, etc. There are many others, time.h for reading the clock, float.h, limits.h... The basic ones are described in most C programming books, you should familiarize yourself with the basic ones as you will need them most often. And remember, Google is your friend.

It is also possible to write your own header files in order to split your program over several files as it grows, and there are also many other seperately available header files for doing more complex things, check out the Gnu C library (GCL) and Gnu Scientific Library (GSL), for example.

Can u plz give me the list of basic library functions?

[sicarie]

Can u plz give me the list of basic library functions?

Did you bother to follow the 'GNU C Library' link above?