---
name: "g3cat"
section: "1"
platform: "linux"
package: "mgetty-fax"
version: "1.2.1-2"
release: "Debian 13 (Trixie)"
platforms: ["linux"]
url: "https://new.carta.tech/g3cat"
---

# g3cat(1)

concatenate multiple g3 documents

## NAME

g3cat - concatenate multiple g3 documents

## SYNOPSIS

g3cat \[-l\] \[-a\] g3-file1 ...

## DESCRIPTION

*g3cat*  concatenates g3 files. These can either be 'raw', that is, bitmaps packed according to the CCITT T.4 standard for one-dimensional bitmap encoding, or 'digifax' files, created by GNU's GhostScript package with the **digifax**  drivers. Its output is a concatenation of all the input files, in raw G3 format, with two white lines in between.

If a - is given as input file, stdin is used.

If the input data is malformed, a warning is printed to stderr, and the output file will have a blank line at this place.

## OPTIONS

- **-l**

  separate files with a one-pixel wide black line.

- **-h \<blank lines\>**

  specifies the number of blank lines *g3cat* should prepend to each page. Default is 0.

- **-L \<lines\>**

  limit lenght of output page to maximum \<lines\> lines.

## SPECIAL-CASE OPTIONS

- **-w \<width\>**

  specifies the desired page width in pixels per line. Default is 1728 PELs, and this is mandatory if you want to send the fax to a standard fax machine. If one of the input files doesn't match this line width (for example because it was created by a broken G3 creator), a warning is printed, and the line width is transparently fixed.

- **-a**

  byte-align the end-of-line codes (EOL) in the file. Every EOL will end at a byte boundary, that is, with a  01 byte.

- **-p \<pad\>**

  specifies a minimum number of bytes that each output line must be padded to.  Padding is done with 0-bits before the EOL code.

- **-R**

  suppress output of end-of-page code (RTC).

## Example

The following example will put a header line on a given g3 page, 'page1' and put the result into 'page2':

echo '$header' \| pbmtext \| pbm2g3 \| g3cat - page1 \>page2

## FILES

\--

## BUGS

Hopefully none :-).

## SEE ALSO

[g32pbm(1)](/g32pbm/1.md), [sendfax(8)](/sendfax/8.md), [faxspool(1)](/faxspool/1.md)

## AUTHORS

*g3cat* is Copyright (C) 1993 by Gert Doering, \<gert@greenie.muc.de\>