What\'s the difference? Which is preferred, or when should I use each one respectively?
exit(1) (usually) indicates unsuccessful termination. However, its usage is non-portable. For example, on OpenVMS, exit(1) actually indicates success.
Only EXIT_FAILURE is the standard value for returning unsuccessful termination, but 1 is used for the same in many implementations.
So to summarize:
If you want to write perfectly portable code use,
EXIT_FAILURE for failure case. While,
You can use either exit(0) or EXIT_SUCCESS for success case.
Note that, EXIT_SUCCESS or 0 are both same.
Reference:
C99 Standard: 7.20.4.3 The exit function
Para 5
Finally, control is returned to the host environment. If the value of status is
zeroorEXIT_SUCCESS, an implementation-defined form of the status successful termination is returned. If the value of status isEXIT_FAILURE, an implementation-defined form of the status unsuccessful termination is returned. Otherwise the status returned is implementation-defined.