Advanced Mac OS X Programming: The Big Nerd Ranch Guide

Inside the Central Loop

Take a look at the central loop in main:

 ​ ​ ​ ​w​h​i​l​e​ ​(​!​f​e​o​f​(​s​t​d​i​n​)​)​ ​{​

Loop over the body of the while statement until the standard-in stream indicates that it has reached EOF (end of file). End of file happens when you explicitly type Control-D on a new line if you are typing text into the program. When in a pipeline, the standard-in stream will be closed when the program writing to it exits or otherwise closes the outgoing pipe on its end.

 ​ ​ ​ ​ ​ ​ ​ ​c​o​n​s​t​ ​s​i​z​e​_​t​ ​l​e​n​g​t​h​ ​=​ ​f​r​e​a​d​ ​(​b​u​f​f​e​r​,​ ​1​,​ ​B​U​F​F​E​R​_​S​I​Z​E​,​ ​s​t​d​i​n​)​;​

Read in no more than BUFFER_SIZE bytes. The fread() function is a record-oriented function that you'll see more of in