krbafs

KAFS(3)			 BSD Library Functions Manual		      KAFS(3)

NAME
     k_hasafs, k_pioctl, k_unlog, k_setpag, k_afs_cell_of_file, krb_afslog,
     krb_afslog_uid - AFS library

LIBRARY
     AFS cache manager access library (libkrbafs, -lkrbafs)

SYNOPSIS
     #include <krbafs.h>

     int
     k_afs_cell_of_file(const char *path, char *cell, int len);

     int
     k_hasafs();

     int
     k_pioctl(char *a_path, int o_opcode, struct ViceIoctl *a_paramsP,
	     int a_followSymlinks);

     int
     k_setpag();

     int
     k_unlog();

     int
     krb_afslog(char *cell, char *realm);

     int
     krb_afslog_uid(char *cell, char *realm, uid_t uid);

DESCRIPTION
     k_hasafs() initializes some library internal structures, and tests for
     the presence of AFS in the kernel, none of the other functions should be
     called before k_hasafs() is called, or if it fails.

     krb_afslog(), and krb_afslog_uid() obtains new tokens (and possibly
     tickets) for the specified cell and realm.	 If cell is NULL, the local
     cell is used. If realm is NULL, the function tries to guess what realm
     to use. Unless you	 have some good knowledge of what cell or realm to
     use, you should pass NULL.	 krb_afslog() will use the real user-id for
     the ViceId field in the token, krb_afslog_uid() will use uid.

     k_afs_cell_of_file() will in cell return the cell of a specified file,
     no more than len characters is put in cell.

     k_pioctl() does a pioctl() syscall with the specified arguments. This
     function is equivalent to lpioctl().

     k_setpag() initializes a new PAG.

     k_unlog() removes destroys all tokens in the current PAG.

RETURN VALUES
     k_hasafs() returns 1 if AFS is present in the kernel, 0 otherwise.
     krb_afslog() and krb_afslog_uid() returns 0 on success, or a kerberos
     error number on failure.  k_afs_cell_of_file(), k_pioctl(), k_setpag(),
     and k_unlog() all return the value of the underlaying system call, 0 on
     success.

ENVIRONMENT
     The following environment variable affect the mode of operation of
     krbafs:

     AFS_SYSCALL  Normally, krbafs will try to figure out the correct system
		  call(s) that are used by AFS by itself.  If it does not
		  manage to do that, or does it incorrectly, you can set this
		  variable to the system call number or list of system call
		  numbers that should be used.

EXAMPLES
     The following code from login will obtain a new PAG and tokens for the
     local cell and the cell of the users home directory.

     if (k_hasafs()) {
	     char cell[64];
	     k_setpag();
	     if(k_afs_cell_of_file(pwd->pw_dir, cell, sizeof(cell)) == 0)
		     krb_afslog(cell, NULL);
	     krb_afslog(NULL, NULL);
     }

ERRORS
     If any of these functions (apart from k_hasafs()) is called without AFS
     beeing present in the kernel, the process will usually (depending on the
     operating system) receive a SIGSYS signal.

SEE ALSO
     Transarc Corporation, "File Server/Cache Manager Interface", AFS-3
     Programmer’s Reference, 1991.

BUGS
     AFS_SYSCALL has no effect under AIX.

KTH-KRB				 May 7, 1997			      KTH-KRB