Table 1 provides a list of environment variables that can be explicitly set by sendmail.
| Environment variable | Description |
|---|---|
| GSK_TRACE | Specifies a bit mask enabling system SSL trace options. |
| GSK_TRACE_FILE | When set to the name of a file in a directory, enables the system SSL trace. |
| HOME | The system initializes this variable at login time to a path name of the user's home directory. |
| HOSTALIASES | The host aliases data set or file. |