Three types of values are required by configuration variables: Boolean, integer, and string. A Boolean is a yes/no value, and is denoted either by “true” and “false,” or “on” and “off.” An integer value is a number; some numbers must be non-negative. A string is a series of characters up to the next newline.
Table 11.4 contains configuration keywords that PGP supports. These keywords can be put into the configuration file, which is normally the file config.txt in the PGPPATH directory. PGP also accepts these configuration values on the command line by preceding the configuration option with a plus (+) and following it with an equal sign (=) and its value. This is described in more detail later in this chapter.
Table 11.4
Configuration Keywords for PGP Startup
| Name
| Type
| Default
| Effect
|
| ARMOR
| Boolean
| off
| When this option is on, data is output encoded in ASCII armor.
|
| ARMORLINES
| integer
| 720
| The number of lines to put in a single ASCII armor block. If there are more than this number of lines, PGP will break up the message into multiple output files.
|
| BAKRING
| string
|
| The directory in which PGP should store backup key rings. In general, this is used to keep a backup key ring on a floppy disk. PGP will then compare the data on the normal key ring with the data in the backup key ring and report errors when they do not match.
|
| CERT_DEPTH
| integer
| 4
| The maximum depth for which certification is valid in the web of trust. This is the maximum level of recursion that PGP will allow.
|
| CHARSET
| string
| noconv
| The character set to use when displaying messages locally. PGP internally uses the Latin-1 charset and converts to external character sets as appropriate. By default, no conversion is done except for MS-DOS, which uses the default charset cp850, not noconv.
|
| CLEARSIG
| Boolean
| on
| When possible, clearsign text messages. If this is off, never clearsign messages. Clearsigning is only possible on text messages when signing with ASCII armor.
|
| COMMENT
| string
|
| When defined, this string will be put in the headers of ASCII armor.
|
| COMPLETES_NEEDED
| integer
| 1
| The number of completely trusted key certifications needed to trust the validity of a public key.
|
| COMPRESS
| Boolean
| on
| When turned on, try to compress all messages when possible. Clearsigned and separate-signature messages are not compressed, but any normal operation will be compressed.
|
| ENCRYPTTOSELF
| Boolean
| off
| Automatically add the originator to the list of recipients when using public key encryption.
|
| INTERACTIVE
| Boolean
| off
| Interactively add keys to the system. By default PGP will add keys in a lump to the key ring. This option allows users to interactively decide which keys to add and which not to add.
|
| KEEPBINARY
| Boolean
| off
| Keep a binary version of the file around. When decrypting an ASCII armor file, PGP will save the binary contents of the ASCII armor to a file.
|
| LANGUAGE
| string
| en
| What language to use when printing messages to the user. By default the program uses English.
|
| MARGINALS_NEEDED
| integer
| 2
| The number of marginally trusted key certifications needed to trust the validity of a key.
|
| MYNAME
| string
|
| The name of the key to use when signing messages. By default, PGP will use the first key on the secret key ring, which is usually the most recently generated key.
|
| PAGER
| string
|
| The pager program to use when printing messages in For Her Eyes Only mode. This option will override the environment variable, PAGER, which in turn overrides the default pager. The default pager is the internal pager except under VMS, which uses Type/Page. Set the PAGER configuration variable to “pgp” to override the environment variable and use the internal pager.
|
| PUBRING
| string
|
| Specifies the location of the public key ring. By default, PGP will look in the PGPPATH directory for the file pubring.pgp. This variable will override the file $PGPPATH/pubring.pgp; PGP will use this file instead.
|
| RANDSEED
| string
|
| Specifies the location of the random number seed file. By default, PGP will look in the PGPPATH directory for randseed.bin. As with PUBRING, PGP will use this file instead of looking in PGPPATH.
|
| SECRING
| string
|
| Specifies the location of the secret key ring file. By default, this option looks in the PGPPATH directory for the file secring.pgp. PGP will use this file instead of looking in PGPPATH.
|
| SHOWPASS
| Boolean
| off
| When on, show the pass phrase as it is being typed. By default, this option is off to protect your pass phrase from being read while you type it.
|
| TEXTMODE
| Boolean
| off
| When turned on, assume a file is a text file. PGP will always check to verify if it is a text file, and will turn off textmode if it is not.
|
| TMP
| string
|
| The directory where temporary files are created. PGP will try to choose a reasonable default if it is not set in the configuration file. On Unix systems, PGP uses the contents of the TMP environment variable; on VMS, PGP will use the contents of SYS$SCRATCH; on DOS, the current directory is used.
|
| TZFIX
| integer
| 0
| The number of hours to add to the time to get GMT. This is needed only if the TZ environment variable does not work.
|
| VERBOSE
| integer
| 1
| The verbosity level of PGP. The more verbose, the more debugging information and progress information is printed to the user. Verbose level 0 is quiet mode, and verbose level 2 provides extra runtime information.
|
