.TH "guncat" "1" "2014" "guncat_0\&.92\&.00\&.tar\&.gz" "guncat \- unencrypting file concatenation"

.PP 
.SH "NAME"
guncat \- catenates files, unencrypting pgp encrypted sections
.PP 
.SH "SYNOPSIS"
\fBguncat\fP [OPTIONS] \f(CW[file(s)]\fP 
.br 
[OPTIONS] \- cf\&. section \fBOPTIONS\fP
.br 
[file(s)] \- optional files to process (cf\&. section \fBINPUT
FILE(S)\fP)
.br 

.PP 
.SH "DESCRIPTION"

.PP 
\fBGuncat\fP 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 \fBgrep\fP(1), or \fBless\fP(1)) may be used to process
those files, but standard tools like \fBcat\fP(1) leave PGP encrypted sections
within such files as\-is\&. As a consequence, browsing the `real\(cq\& contents (i\&.e\&.,
clear\-text sections and the unencrypted contents of PGP encrypted sections) of
those files is difficult\&.
.PP 
\fBGuncat\fP acts like \fBcat\fP, but unencrypts encrypted sections encountered in the
files processed by \fBguncat\fP, copying the unencrypted information to \fBguncat\fP\(cq\&s standard
output stream, which may thereupon be processed by other tools\&.
.PP 
PGP/GPG encrypted sections are surrounded by 
.nf 

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

.fi 
and
.nf 

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

.fi 
markers\&. Whenever \fBguncat\fP encounters such
sections they will be processed by \fBgpg\fP(1)\&. \fBGpg\fP needs a passphrase to
unencrypt such sections\&. The required passphrase may be provided to \fBguncat\fP, which
will then forward the passphrase to \fBgpg\fP, or \fBgpg\fP will itself ask for
the required passphrase\&.
.PP 
When providing an incorrect passphrase to \fBguncat\fP two additional attempts to
provide the correct passphrase are granted\&. If the third attempt also fails,
\fBguncat\fP 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 \fIseekable\fP\&. If the
file does not support seeking operations then \fBguncat\fP also terminates\&.
.PP 
.SH "RETURN VALUE"

.PP 
\fBGuncat\fP returns 0 to the operating system unless an error occurs (0 is also
returned when usage info (option \f(CW\-\-help\fP), \fBguncat\fP\(cq\&s version number (option
\f(CW\-\-version\fP), or the configured \fBgpg\fP call (option \f(CW\-\-show\-gpg\fP) is
requested\&.
.PP 
.SH "INPUT FILE(S)"

.PP 
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 \f(CW\-\-passphrase\fP is specified the standard input stream\(cq\&s
first line is used as \fBgpg\fP\(cq\&s passphrase\&.
.PP 
Any other argument is considered a file (path specifications are allowed) 
to be processed in sequence by \fBguncat\fP\&. 
.PP 
If an argument does not refer to a readable file, \fBguncat\fP terminates with an
error message\&.
.PP 
.SH "OPTIONS"

.PP 
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\&.
.IP o 
\fB\-\-gpg\fP=\f(CWpath\fP
.br 
Path to the \fBgpg\fP program (default: \f(CW/usr/bin/gpg\fP)
.IP 
.IP o 
\fB\-\-gpg\-msg\fP=\f(CWpath\fP (\fB\-m\fP)
.br 
Path to where \fBgpg\fP should write its messages\&. Specify \- to write
the messages to the standard error stream\&. By default messages are
suppressed\&. 
.IP 
.IP o 
\fB\-\-gpg\-no\-batch\fP
.br 
Option \f(CW\-\-batch\fP is omitted when calling \fBgpg\fP\&.
.IP 
.IP o 
\fB\-\-gpg\-option\fP=\f(CWoption\fP (\fB\-m\fP)
.br 
Add \f(CWoption\fP to \fBgpg\fP\(cq\&s call\&. If the option contains blanks, surround
\f(CWoption\fP by single or double quotes\&.
.IP 
.IP o 
\fB\-\-help\fP (\fB\-h\fP)
.br 
Basic usage information is written to the standard output stream\&.
.IP 
.IP o 
\fB\-\-locate\-keys\fP \fB\-l\fP
.br 
Locate missing public keys at the configured key server(s) (by default
missing keys are not searched for)\&.
.IP 
.IP o 
\fB\-\-passphrase\fP \fB\-p\fP
.br 
The passphrase is read as the first line from the standard input stream
(without being echoed); otherwise the passphrase is handled by \fBgpg\fP
itself (e\&.g\&., using \fBgpg\-agent\fP(1))\&.
.IP 
.IP o 
\fB\-\-show\-gpg\fP
.br 
Show the gpg command that would be used, and quit, returning 0\&.
.IP 
.IP o 
\fB\-\-tty\-OK\fP \fB\-t\fP
.br 
Option \f(CW\-\-no\-tty\fP is omitted when calling \fBgpg\fP\&.
.IP 
.IP o 
\fB\-\-verbose\fP=\f(CW[0\-2]\fP
.br 
Specifies \fBgpg\fP\(cq\&s verbosity level\&. When calling \fBgpg\fP, by default
\f(CW\-\-quiet\fP is specified; with \f(CW\-\-verbose 0\fP \fBgpg\fP\(cq\&s option
\f(CW\-\-no\-verbose\fP is specified; otherwise \f(CW\-\-verbose\fP is specified
once or twice\&.
.IP 
.IP o 
\fB\-\-version\fP (\fB\-v\fP)
.br 
\fBGuncat\fP\(cq\&s version number is written to the standard output stream\&.

.PP 
.SH "SEE ALSO"

.PP 
\fBcat\fP(1), \fBgpg\fP(1), \fBgpg\-agent\fP(1), \fBgrep\fP(1), \fBless\fP(1)\&.
.PP 
.SH "BUGS"
None reported
.PP 
.SH "COPYRIGHT"
This is free software, distributed under the terms of the `GNU General
Public License\(cq\&\&. Copyright remains with the author\&. \fBGuncat\fP is available at
\f(CWhttp://guncat\&.sourceforge\&.net/\fP\&.
.PP 
.SH "ORGANIZATION"
Center for Information Technology, University of Groningen\&.
.PP 
.SH "AUTHOR"

    Frank B\&. Brokken (\fBf\&.b\&.brokken@rug\&.nl\fP)\&.