TECHPULP | Constructor and Destructor for C Program

October 08, 2008

By: Neo

In Category C/C++

constructor and destructor attributes can be used to define a constructor function and a destructor function for a C program. In the following example pg_init function is defined as constructor and this function gets invoked before main() function. The pg_deinit function is defined as destructor and it gets invoked before process exits.
Download: condes.c

#include <stdio.h>

static void pg_init () __attribute__ ((constructor));
static void pg_deinit () __attribute__ ((destructor));

static void
pg_init()
{
        printf("program init...........\n");
}

static void
pg_deinit()
{
        printf("program deinit...........\n");
}

int main()
{
        printf("This is main\n");
}

The following is the output.

[neo@techpulp ~]# gcc condes.c -o condes
[neo@techpulp ~]#
[neo@techpulp ~]# ./condes
program init...........
This is main
program deinit...........
[neo@techpulp ~]#

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