mikeage.net @ כ"ד מרחשון תשס"ט

Sometimes, you'll have a scenario with two variables, and you need to use one of them based on a simple test. Rather than a long and awkward if / else statement, C allows the use of the ? : form. It is perfectly acceptable to write:

int i,j,k,l;
...
i = (j > 5? k : l)

which will set i to k if j is greater than 5, and l otherwise.
Another common use is [sf]?printf statements:

printf("The test %s\n",(status == OK) ? "passed" : "failed");

However, one can't use it to handle selective assignments. The following code is illegal:

int i,j,k;
...
((i>5) ? j : k) = 5;

This cannot be used to choose whether j or k is set to 5.
There is, however a way this can be done. Using pointer, we can select which one to deference:

*((i>5) ? &j : &k) = 5;

This will work.