What was the specific vow that Cholkar made, and how did he observe it before his trip to Shirdi?

According to Chapter 15, a man named Cholkar made a vow to visit Shirdi. As a form of penance and commitment to this vow, he decided to abstain from sugar, which he considered an 'inedible substance' until he could fulfill his promise. The text highlights his dedication by noting that he even drank his tea without sugar during this period. This act of renunciation was a secret penance he undertook due to the long delay in his journey. Upon finally arriving in Shirdi, he completed his vow by having Sai Baba's darshan, prostrating at His feet, and distributing sugar and offering a coconut with a pure heart.