title: Linux / C Check if a char contains spaces, the newline character or the tab character
body: <p>I have a GtkEntry where the user has to enter an IP number or a hostname. When the button is pressed what the user typed into the entry is added to a char. How can I programmatically check if this char contains spaces, the newline character or the tab character? I don't need to remove them, just to know if they exist. Thanks in advance!</p>