After some macro definitions that I do not list here the start of the function main comes:
. . . . variable declarations . . . . .
pSbProgram pProgram;
. . . . variable declarations . . . . .
main(int argc, char *argv[], char *env[]){
This piece of code defines the local variables. The variable pProgram will hold the pointer to the program object or simply saying pProgram is the program object variable. The other variables are not described here, their names and the code where they are used should make their usage and purpose clear.