In the Encyclopedic dictionary authored by T.V. Sambasivam Pillai (Reference 1), a strange story is told.
" Machamuni is a siddhar. He was the child brought up by Pinnakeesar. He is also Pinakeesar's disciple. There is a story that once Lord Siva was preaching Uma Devi. Uma Devi had slept when Lord Siva was preaching her. However, a fish was listening to the lecture. Later on that fish was transformed into Siddhar Machamuni by Lord Siva."
Although it is a story, it is very interesting indeed.
In the 523rd song of " Karuvoorar Vadha Kaviyam ", Karuvoorar says that Machamuni is a Sembadavar (Presently categorized under backward classes by Government of Tamil Nadu in Government Order 36, 1996). Sembadavar's are traditional fisherman. From the name Machamuni, it is easy to say that he is a fisherman (Macham mean fish in Tamil). Siddhar Agasthiar in the 218th song of his book " Amudha Kalai Ganam " says that Machamuni belongs to Sembadavar social group.
However, siddhar Bogar in the 5700th song of " Bogar 7000 ", says that he belongs to " Kalludayar " social group (The author of this article is unable to understand the exact meaning of this song). Also in song 5873, he says that Machamuni was born on the Rohini star in the Tamil month of Adi (July-August).
Machamuni in his 97th song of his book " Machamuni Thandagam 100 ", mentions the words "Guru Nandhi" and "Guru Bogar", while offering prayers to his guru. Hence, it can be said that Siddhar Bogar and Siddhar Nandeeswarar were his gurus.
Machamuni also mentions about the Siva Thandava witnessed by siddhar Pathanjali in one of his songs. Hence, it can be said that he had lived in the period when siddhar Pathanjali and Sri Viyakrabathar witnessed the Siva Thandava in Thillai. Thillai is the other name of Chidambaram and is one of the 5 dance halls of Lord Siva.
In the book " Agasthiar 12000 ", in the fifth Kandam, siddhar Agasthiar says that Machamuni had taken lessons from Kaga Bugandar. He also says that he donated all his wealth to poor people on attaining spiritual salvation. Machamuni attained samadhi at Thiruparankundram.
Some of the books written by Machamuni are