guncat

guncat_1.01.02.tar.gz

2014-2015

guncat(1)

guncat_1.01.02.tar.gz guncat - unencrypting file concatenation

2014-2015

NAME

SYNOPSIS

DESCRIPTION

Guncat was designed to tackle a problem encountered with (partically) PGP encrypted files (which may be encountered in, e.g., mailboxes). Tools to process text-files (like grep(1), or less(1)) may be used to process those files, but standard tools like cat(1) leave PGP encrypted sections within such files as-is. As a consequence, browsing the `real' contents (i.e., clear-text sections and the unencrypted contents of PGP encrypted sections) of those files is difficult.

Guncat acts like cat, but unencrypts encrypted sections encountered in the files processed by guncat, copying the unencrypted information to guncat's standard output stream, which may thereupon be processed by other tools.

PGP/GPG encrypted sections are surrounded by

-----BEGIN PGP MESSAGE-----

-----END PGP MESSAGE-----

When providing an incorrect passphrase to guncat two additional attempts to provide the correct passphrase are granted. If the third attempt also fails, guncat terminates. Furthermore, when an incorrect passphrase is provided, the currently processed file must be reset to the beginning of the encrypted section. This implies that the processed file must be seekable. If the file does not support seeking operations then guncat also terminates.

RETURN VALUE

Guncat returns 0 to the operating system unless an error occurs (0 is also returned when usage info (option --help), guncat's version number (option --version), or the configured gpg call (option --show-gpg) is requested.

INPUT FILE(S)

When no file arguments are provided (or when - is provided) the standard input stream is processed. Note that when the standard input stream is specified and option --passphrase is specified the standard input stream's first line is used as gpg's passphrase.

Any other argument is considered a file (path specifications are allowed) to be processed in sequence by guncat.

If an argument does not refer to a readable file, guncat terminates with an error message.

OPTIONS

Where available, single letter options are listed between parentheses following their associated long-option variants. Single letter options require arguments if their associated long options require arguments as well.

• --gpg=path
  Path to the gpg program (default: /usr/bin/gpg)

• --gpg-msg=path (-m)
  Path to where gpg should write its messages. Specify - to write the messages to the standard error stream. By default messages are suppressed.

• --gpg-no-batch
  Option --batch is omitted when calling gpg.

• --gpg-option=option (-m)
  Add option to gpg's call. If the option contains blanks, surround option by single or double quotes.

• --help (-h)
  Basic usage information is written to the standard output stream.

• --locate-keys -l
  Locate missing public keys at the configured key server(s) (by default missing keys are not searched for).

• --passphrase -p
  The passphrase is read as the first line from the standard input stream (without being echoed); otherwise the passphrase is handled by gpg itself (e.g., using gpg-agent(1)).

• --show-gpg
  Show the gpg command that would be used, and quit, returning 0.

• --tty-OK -t
  Option --no-tty is omitted when calling gpg.

• --verbose=[0-2]
  Specifies gpg's verbosity level. When calling gpg, by default --quiet is specified; with --verbose 0 gpg's option --no-verbose is specified; otherwise --verbose is specified once or twice.

• --version (-v)
  Guncat's version number is written to the standard output stream.

SEE ALSO

cat(1), gpg(1), gpg-agent(1), grep(1), less(1).

BUGS

COPYRIGHT

ORGANIZATION

AUTHOR