The password field may not be filled if shadow passwords have been enabled\&. If shadow passwords are being used, the encrypted password will be found in \fI/etc/shadow\fR\&. The encrypted password consists of characters from the 64 characters alphabet a thru z, A thru Z, 0 thru 9, \\\&. and /\&. Optionally it can start with a "$" character\&. This means the encrypted password was generated using another (not DES) algorithm\&. For example if it starts with "$1$" it means the MD5\-based algorithm was used\&. Refer to \fBcrypt\fR(3) for details on how this string is interpreted\&.
The home directory field provides the name of the initial working directory\&. \fILogin\fR uses this information to set the value of the \fB$HOME\fR environmental variable\&.
The command interpreter field provides the name of the user's command language interpreter, or the name of the initial program to execute\&. \fILogin\fR uses this information to set the value of the \fB$SHELL\fR environmental variable\&. If this field is empty, it defaults to the value \fI/bin/sh\fR\&.