Experience in C Programming in Linux-triggering time of the custom exit function registered by atexit

We all know that we can use atexit to register a function we write as the exit function. That is to say, when the program exits, it will call our custom exit function. The problem is:

There are two common methods to end a C program in Linux:

1. Call return in the main function
2. Call "exit" system call anywhere

The test proves that both methods will trigger our custom exit function. The written test program is as follows:

Code: select all

# Include "apue. H"

Static void my_exit (void );

Int main (void)
{
If (atexit (my_exit )! = 0)
Err_sys ("can't register my_exit ");

Return 0;
Printf ("Main is done \ n ");
// Return 0;
}

Static void my_exit (void)
{
Printf ("stuff print in my_exit \ n ");
}

Refer to the p150 page of apue2 for more details and examples.