What was the vow that Cholkar made, and what personal sacrifice did he undertake until he could fulfill it?

Facing a critical examination that would determine the permanency of his job, Cholkar made a firm resolve and vow to Sai Baba. As Chapter 15 narrates, he promised that if he passed the exam through Baba's grace, he would present himself at Baba's feet in Shirdi and distribute sugar candy (khadisakhar) in His name. After his wish was granted and he passed, he was delayed in fulfilling the vow due to financial difficulties. During this waiting period, Cholkar undertook a significant personal sacrifice: he completely gave up sugar. The text explicitly states that until the vow was fulfilled, Cholkar avoided sugar as an "inedible substance" and even drank his tea without it.