changing variable value from within a function

Question

I'm writing a program in c in which I need to change the value of a variable from within a function.

I've tried setting the variable globally but it was not recognized withinn the function

So I tried the following: the variable is nobuttons:

readconfig(config2, &nobuttons);

void readconfig(FILE * config, int * buttons) {
    buttons = 5;
}

when I print the value of buttons, it's shown as 0(the value it was initialized to)

what am I doing wrong?

Compile with warnings set to their highest level.

Jim Balter
– Jim Balter

2015-07-02 02:44:08 +00:00
Commented Jul 2, 2015 at 2:44 — Jim Balter
– Jim Balter, Commented Jul 2, 2015 at 2:44

mazhar islam · Accepted Answer · 2015-07-02 02:49:10Z

7

Use *buttons = 5; instead of buttons = 5;

when I print the value of buttons, it's shown as 0(the value it was initialized to)

The value of button is not initialized but as you know, the global variables by default initialized with 0 hence you get 0 when you print it.

buttons=5; means the address of buttons pointer now holding address 5 whereas, *buttons = 5; means the content of buttons pointer is changed with value 5. Remember, the content of whom buttons pointer points will be updated by 5 now.

edited Jul 2, 2015 at 2:49

answered Jul 2, 2015 at 2:35

mazhar islam

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