C Library Functions                                     crypt(3C)



NAME
     crypt - string encoding function

SYNOPSIS
     #include <unistd.h>

     char *crypt(const char *key, const char *salt);

DESCRIPTION
     The crypt() function is a  string  encoding  function,  used
     primarily for password encryption.  It is based on a one-way
     encryption algorithm with variations intended  (among  other
     things)  to  frustrate  use of hardware implementations of a
     key search.

     The _k_e_y argument points to a string to be encoded (for exam-
     ple,  the  user's password.) Only the first eight characters
     are used; the rest are ignored. The _s_a_l_t is a  two-character
     string  chosen  from  the  set [a-zA-Z0-9./]. This string is
     used to perturb the hashing algorithm in one  of  4096  dif-
     ferent ways.

RETURN VALUES
     Upon successful completion, crypt() returns a pointer to the
     encoded  string.  The  first  two characters of the returned
     value are those of the _s_a_l_t argument. Otherwise it returns a
     null pointer and sets errno to indicate the error.

     In multithreaded applications, the return value is a pointer
     to thread-specific data.

ERRORS
     The crypt() function will fail if:

     ENOSYS    The functionality is not supported on this  imple-
               mentation.

USAGE
     The return value of crypt() points to static  data  that  is
     overwritten by each call.

     The values returned by this function  may  not  be  portable
     among XSI-conformant systems.

ATTRIBUTES
     See attributes(5) for descriptions of the  following  attri-
     butes:








SunOS 5.7           Last change: 29 Dec 1996                    1






C Library Functions                                     crypt(3C)



     ____________________________________________________________
    |       ATTRIBUTE TYPE        |       ATTRIBUTE VALUE       |
    |______________________________|______________________________|
    | MT-Level                    | Safe                        |
    |______________________________|______________________________|

SEE ALSO
     passwd(1), crypt(3X), encrypt(3C), getpass(3C),  setkey(3C),
     passwd( 4), attributes(5)














































SunOS 5.7           Last change: 29 Dec 1996                    2