What is equivalent of Santhara(Sallekhanā) in Hinduism?

Question

There is a concept of Santhara(Sallekhanā or Sanyasana-marana) in Jain community.

It is the last vow prescribed by the Jain ethical code of conduct.The vow of sallekhanā is observed by the Jain ascetics and lay votaries at the end of their life by gradually reducing the intake of food and liquids.

According to Jain text, Puruṣārthasiddhyupāya:

When death is imminent, the vow of sallekhanā is observed by progressively slenderizing the body and the passions. Since the person observing sallekhanā is devoid of all passions like attachment, it is not suicide.

The initial though that came to my mind of equivalent of Santhara practised in Hinduism was the concept of Samādhi, but looking at the description of it on Wiki, I am now thinking that there exists few differences.

As per Wiki, Samādhi

refers to a state of meditative consciousness. It is a meditative absorption or trance, attained by the practice of dhyāna.

Is there any equivalent of Santhara practised in Hinduism?

Answer 1

The Manu Smriti says in its chapter 6 that a Brahmin,residing in forest and living the life of an ascetic ,may end his life by fasting till death.

6.29. These and other observances must a Brahmana who dwells in the forest diligently practise, and in order to attain complete (union with) the (supreme) Soul, (he must study) the various sacred texts contained in the Upanishads,

6.30. (As well as those rites and texts) which have been practised and studied by the sages (Rishis), and by Brahmana householders, in order to increase their knowledge (of Brahman), and their austerity, and in order to sanctify their bodies;

6.31. Or let him walk, fully determined and going straight on, in a north-easterly direction, subsisting on water and air, until his body sinks to rest.

And the practice of getting rid of body in that manner is extolled in the following verse:

6.32. A Brahmana, having got rid of his body by one of those modes practised by the great sages, is exalted in the world of Brahman, free from sorrow and fear.

Answer 2

There is a similar reference in the Manusmriti, verse 6.31:

अपराजितां वाऽस्थाय व्रजेद् दिशमजिह्मगः ।
आ निपातात्शरीरस्य युक्तो वार्यनिलाशनः ॥ ३१ ॥

aparājitāṃ vā'sthāya vrajed diśamajihmagaḥ |
ā nipātātśarīrasya yukto vāryanilāśanaḥ || 31 ||

Or, having fixed upon the North-Easterly direction, he shall go forward, moving straight on, intent and living upon water and air,—till the falling off of his body.—(31).

Of which the commentary by Medhatithi says:

‘Intent, living upon water and air, till the falling off of the body.’—That is, until the body falls off, he shall live upon air and on water.

‘Intent’,—having concentrated himself by the rules of Yoga.

This refers to the ‘Grand Journey’ (towards certain death).—(31).

I am not in possession of the Sanskrit text, so I do not know what word or term has been used to represent "Grand Journey".

There is another work, called the Sanatkumara-samhita, which refers to a similar practice:

bahu-varṣa-sahasreṣu śāka-mūla-phalāśinā |
śuṣka-parṇāmbu-vāyv-ādi- bhoginā ca nirāśinā || 4 ||
strīṇāṃ sandarśanālāpa- varjinā bhūmi-śāyinā |
kāmādi-sad-guṇān jitvā bahyendriyān niyamya ca || 5 ||

At first I ate only wild vegetables, roots, and fruits, then I ate only dry leaves, then I only drank water, then I only breathed air, and finally I neither ate, drank, nor breathed.

I neither saw nor spoke to women. I slept on the ground. I conquered the six vices, beginning with lust, and I controlled the external senses.

The Sanatkumara-samhita forms part of the Shiva-samhita.

Answer 3

Yes there is smilar concept as "Santhara(Sallekhanā or Sanyasana-marana)" in Hinduism.It's called "Anashan" (अनशन) Vrata .The meaning of word Anashan is discard or to stop intake of any food. See Here

This is described as a vrata to take in the time of very old age or Vanaprastha person (retiring into a forest"). This is described in details in Shreemad Bhagvat Purana (Skanda 7 Chapter 12 Shlokas 23 to 31) The chapter name is "Rules of Brahmacharya & Vaanprastha Ashrama"

There is also mentioning of Story of King Parikshita took this vrata & took fast (till death) after he realised that he is going to die by snake bite after 7 days. These rules are told by Sage Narada , also there is a reason provided about who should take this Vrata. 

यदाकल्प: स्वक्रियायां व्याधिभिर्जरयाथवा ।
   अन्विक्षिकयां वा विद्यायां कुर्यादनशनादिकम ॥23॥
 
  yadākalpaḥ sva-kriyāyāṁ vyādhibhir jarayāthavā ānvīkṣikyāṁ vā vidyāyāṁ kuryād anaśanādikam
 
    Meaning -When because of disease or old age one is unable to perform his prescribed duties for advancement in spiritual consciousness or study of the Vedas, he should practice fasting, not taking any food.

SB 7.12.23 (anaśana-ādikam = not take sufficient food.)