Appellant Pope, an inmate of Leavenworth penitentiary serving a 25-year sentence imposed by the United States District Court for the Western District of Texas, brought this action against prison officials for a declaratory judgment and injunctive relief to establish his right to mail a letter to the chief probation officer at San Antonio, Texas, relating to the preparation of a presentence report and the delivery of that report to the sentencing judge. The district court sustained a motion to dismiss.

The letter sought information for use in a contemplated, but unfiled, motion under 28 U.S.C. § 2255. The appellee officials determined that the letter was unmailable under prison regulations. Although we see no harm in the letter *297 and are doubtful of the wisdom of the denial of the mailing privilege, we do not have the power through the injunctive process to supervise the conduct of a federal penitentiary or its discipline. 1 That power lies in the Attorney General and the Bureau of Prisons. 2 Control over a prisoner’s mail is basically an administrative function. 3 The action taken here does not violate any constitutional right of the prisoner. If the information sought by the prisoner is available, means exist to obtain it in a § 2255 application.

Affirmed.