Injunctions are governed by Sections 37, 38, 39 to Section 42 of Specific Relief Act. These sections are reproduced as under-

Section 37: Temporary and Perpetual Injunctions-

(1) Temporary injunctions are such as are to continue until a specifie time, or until the further order of the court, and they may be granted at any stage of a suit and are governed by the Code of Civil Procedure, 1908.

(2) A perpetual injunction can only be granted by the decree made at the hearing and upon the merita of the suit; the defendant is thereby perpetually enjoined from the asaertion of a right, or from the commission of an act, which would be contrary to the rights of the plaintiff.
 

Section 38: Perpetual Injunction is granted under the following Circumstances:

(1) Subject to the other provisions contained in or referred to by this Chapter, a perpetual injunction may be granted to the plaintiff to prevent an existing breach of obligation in his favour, whether expressly or by implication.

(2) From contract When any such obligation arises, than rules and provisions contained in Chapter II will be followed by the court.

(3) When plaintiff's right is invaded or threatens to invaded by the defendant or enjoyment of property, the court may grant a perpetual injunction in the following cases, namely:
(a) where trustee of the plaintiff's property is the defendant,

(b) Where actual damage caused cannot be ascertained, or likely to be caused by the invasion;

(c) In Such matters where invasion is such that compensation in terms of money would not afford adequate relief;

(d) where to prevent a multiplicity of judicial proceedings injunction is necessary.
 

Section 39: Mandatory Injunctions-

When, to prevent the breach the breach of an obligation, it is necessary to compel the performance of certain acts which the court is capable of enforcing, the court may grant an injunction to prevent the breach complained in its discretion and also to compel performance of the requisite acts.
 

Section 40. in addition to or Damages in lieu of, injunction-

(1) A suit for perpetual injunction in the plaintiff under section 38, or under section 39 - mandatory injunction, may claim damages either in addition to, or in substitution for, the Court may for such injunction, if it thinks fit, award such damages.

(2) unless The plaintiff has claimed such relief in his plaint, No relief for damages shall be granted under this section:

Provided in the plaint no such damages have been claimed, the Court shall, at any stage of the proceeding, allow the plaintiff to amend the plaint on such conditions as may be apt for inserting such claim.

(3) The dismissal of a suit to stop the breach of an obligation existing in favour of the plaintiff shall block his right to sue for damages for such breach.
 

Section 41, Injunction when refused:

An injunction cannot be granted-
(a) to stop any person from prosecuting a judicial proceeding pending at the institution of the suit in which the injunction is sought, unless such it is necessary for such refrain to prevent a multiplicity of proceedings.

(b) to refrain any person from instituting or prosecuting any proceeding in a Court which is not subordinate to that from which the injunction is sought;

(c) to refrain anyone from applying to any legislative body;

(d) to refrain any person from instituting or prosecuting any proceeding in a criminal matter

(e) to avoid the breach of a contract whose performance would not be specifically enforced;

(f) to prevent a nuisance, an act of which it is not reasonably clear that it will be a nuisance;

(g) to stop a continuing breach in which the plaintiff has acquiesced;

(h) except in case of breach of trust, when equally efficacious relief can certainly be obtained by any other usual mode of proceeding;

(i) when the conduct his agent or of the plaintiff has been such as that to disentitle him to approach the Court.

(j) when there is no personal interest in the matter of the plaintiff.
 

Section 42. Injunction to perform negative agreement:

Notwithstanding anything contained in section 41(e), where a contract comprises an affirmative agreement to do a certain act, coupled with a negative agreement, express or implied, not to do a certain act, the circumstance that the court is unable to compel specific performance of the affirmative agreement shall not preclude it from granting an injunction to perform the negative agreement;

Provided what is binding on the plaintiff he has not failed to perform the contract.

The provisions contained in Order 39 Rules 1 to 5, deal with grant of temporary injunction. The same are reproduced as under:
 

Order 39 Rule 1, Cases in which temporary injunction may be g ranted:-

Where by affidavit or otherwise proved in any suit;
(a) that any property in dispute in a suit is in danger of being wasted damaged or alienated by any party to the suit, or wrongfully sold execution of a decree, or

(b) that the defendant threatens, or intends, to remove or dispose of his execution of a decree, or property with a view to defrauding his creditor,

(c) that the plaintiff is threatened by the defendant to dispossess, or otherwise cause injury to the plaintiff in relation to any property in dispute in the suit, the Court may to restrain such act by order grant a temporary injunction, or make such other order for the purpose of staying and preventing the wasting, damaging, alienation, sale, removal or disposition of the property or dispossession of plaintiff or other wise causing injury to the plaintiff in relation to any property in dispute in the suit as the Court thinks fit, until the disposal of the suit or until such other further orders.
 

Order 39 Rule 2:- To restrain repetition or continuance of breach grant of Injunction -

(1) In any suit for restraining the defendant from committing a breach of contract or other injury of any kind, whether compensation is claimed in the suit or not, the plaintiff may, at any time after the commencement of the suit, and either before or after judgment, apply to the Court for a temporary injunction to restrain the defendant from committing the breach of contract or injury complained of, or any breach of contract or injury of a like kind arising of the same contract or relating to the same property or right.

(2) The Court may by order grant such injunction, on such terms as to the duration of the injunction, keeping an account, giving security, or otherwise as the Court thinks fit.

Also read:
Injunction and Extra Judicial Remedies under Tort Law:
An injunction is an order of a court restraining the commission, repetition or continuance of a wrongful act of the defendant.