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|
This is barcode.info, produced by makeinfo version 4.0b from
barcode.texinfo.
This file is the User's Manual for the barcode library (version
0.98).
File: barcode.info, Node: Top, Next: Overview, Prev: (dir), Up: (dir)
Barcode tools
*************
This file documents version 0.98 of the barcode library and sample
programs (March 2002).
* Menu:
* Overview::
* The Barcode Object::
* Supported Flags::
* The API::
* The barcode Executable::
* Supported Encodings::
* PCL Output::
* Bugs and Pending Issues::
File: barcode.info, Node: Overview, Next: The Barcode Object, Prev: Top, Up: Top
Overview
********
The "barcode" package is mainly a C library for creating bar-code
output files. It also includes a command line front-end and (in a
foreseeable future) a graphic frontend.
The package is designed as a library because we think the main use
for barcode-generation tools is inside more featured applications. The
library addresses bar code printing as two distinct problems: creation
of bar information and actual conversion to an output format. To this
aim we use an intermediate representation for bar codes, which is
currently documented in the `ps.c' source file (not in this document).
Note that the library and the accompanying material is released
according to the GPL license, not the LGPL one. A copy of the GPL is
included in the distribution tarball.
File: barcode.info, Node: The Barcode Object, Next: Supported Flags, Prev: Overview, Up: Top
The Underlying Data Structure
*****************************
Every barcode-related function acts on a data structure defined in
the `barcode.h' header, which must be included by any C source file
that uses the library. The header is installed by make install.
The definition of the data structure is included here for reference:
struct Barcode_Item {
int flags; /* type of encoding and other flags */
char *ascii; /* malloced */
char *partial; /* malloced too */
char *textinfo; /* information about text placement */
char *encoding; /* code name, filled by encoding engine */
int width, height; /* output units */
int xoff, yoff; /* output units */
int margin; /* output units */
double scalef; /* requested scaling for barcode */
int error; /* an errno-like value, in case of failure */
};
The exact meaning of each field and the various flags implemented are
described in the following sections.
Even though you won't usually need to act on the contents of this
structure, some of the functions in the library receive arguments that
are directly related to one or more of these fields.
* Menu:
* The Field List::
* The Intermediate Representation::
File: barcode.info, Node: The Field List, Next: The Intermediate Representation, Prev: The Barcode Object, Up: The Barcode Object
The Fields
==========
`int flags;'
The flags are, as you may suspect, meant to specify the exact
behaviour of the library. They are often passed as an argument to
barcode functions and are discussed in the next section.
`char *ascii;'
`char *partial;'
`char *textinfo;'
`char *encoding;'
These fields are internally managed by the library, and you are
not expected to touch them if you use the provided API. All of
them are allocated with malloc.
`int width;'
`int height;'
They specify the width and height of the active barcode region
(i.e., excluding the white margin), in the units used to create
output data (for postscript they are points, 1/72th of an inch,
0.352 mm). The fields can be either assigned to in the structure
or via Barcode_Position(), at your choice. If either value or
both are left to their default value of zero, the output engine
will assign default values according to the specified scaling
factor. If the specified width is bigger than needed (according to
the scaling factor), the output barcode will be centered in its
requested region. If either the width of the height are too small
for the specified scale factor, the output bar code will expand
symmetrically around the requested region.
`int xoff;'
`int yoff;'
The fields specify offset from the coordinate origin of the output
engine (for postscript, position 0,0 is the lower left corner of
the page). The fields can be either assigned to in the structure
or via Barcode_Position(), at your choice. The offset specifies
where the white margin begins, not where the first bar will be
printed. To print real ink to the specified position you should
set margin to 0.
`int margin;'
The white margin that will be left around the printed area of the
bar code. The same margin is applied to all sides of the printed
area. The default value for the margin is defined in `barcode.h'
as BARCODE_DEFAULT_MARGIN (10).
`double scalef;'
The enlarge or shrink value for the bar code over its default
dimension. The width and scalef fields interact deeply in the
creation of the output, and a complete description of the issues
appears later in this section.
`int error;'
The field is used when a barcode function fails to host an
errno-like integer value.
Use of the width and scalef fields.
-----------------------------------
A width unit is the width of the thinnest bar and/or space in the
chosen code; it defaults to 1 point if the output is postscript or
encapsulated postscript.
Either or both the code width and the scale factor can be left
unspecified (i.e., zero). The library deals with defaults in the
following way:
Both unspecified
If both the width and the scale factor are unspecified, the scale
factor will default to 1.0 and the width is calculated according
to the actual width of the bar code being printed.
Width unspecified
If the width is not specified, it is calculated according to the
values of scalef.
Scale factor unspecified
If the scale factor is not specified, it will be chosen so that
the generated bar code exactly fits the specified width.
Both specified
The code will be printed inside the specified region according to
the specified scale factor. It will be aligned to the left. If,
however, the chosen width is too small for the specific bar code
and scaling factor, then the code will extend symmetrically to the
left and to the right of the chosen region.
File: barcode.info, Node: The Intermediate Representation, Prev: The Field List, Up: The Barcode Object
The Intermediate Representation
===============================
The encoding functions print their output into the partial and
texinfo fields of the barcode data structure. Those fields, together
with position information, are then used to generate actual output.
This is an informal description of the intermediate format.
The first char in partial tells how much extra space to add to the
left of the bars. For EAN-13, it is used to leave space to print the
first digit, other codes may have '0' for no-extra-space-needed.
The next characters are alternating bars and spaces, as multiples of
the base dimension which is 1 unless the code is rescaled. Rescaling is
calculated as the ratio from the requested width and the calculated
width. Digits represent bar/space dimensions. Lower-case letters
represent those bars that should extend lower than the others: 'a' is
equivalent to '1', 'b' is '2' and so on up to 'i' which is equivalent to
'9'. Other letters will be used for encoding-specific meanings, as soon
as I implement them.
The textinfo string is made up of fields %lf:%lf:%c separated by
blank space. The first integer is the x position of the character, the
second is the font size (before rescaling) and the char item is the
character to be printed.
Both the partial and textinfo strings may include "-" or "+" as
special characters (in textinfo the char should be a stand-alone word).
They state where the text should be printed: below the bars ("-",
default) or above the bars. This is used, for example, to print the
add-5 and add-2 codes to the right of UPC or EAN codes (the add-5
extension is mostly used in ISBN codes).
File: barcode.info, Node: Supported Flags, Next: The API, Prev: The Barcode Object, Up: Top
The Flags
*********
The following flags are supported by version 0.98 of the library:
`BARCODE_ENCODING_MASK'
The mask is used to extract the encoding-type identifier from the
flags field.
`BARCODE_EAN'
`BARCODE_UPC'
`BARCODE_ISBN'
`BARCODE_128B'
`BARCODE_128C'
`BARCODE_128'
`BARCODE_128RAW'
`BARCODE_39'
`BARCODE_I25'
`BARCODE_CBR'
`BARCODE_MSI'
`BARCODE_PLS'
`BARCODE_93'
The currently supported encoding types: EAN (13 digits, 8 digits,
13 + 2 add-on and 13 + 5 add-on), UPC (UPC-A, UPC-E, UPC-A with 2
or 5 digit add-on), ISBN (with or without the 5-digit add-on),
CODE128-B (the whole set of printable ASCII characters), CODE128-C
(two digits encoded by each barcode symbol), CODE128 (all ASCII
values), a "raw-input" pseudo-code that generates CODE128 output,
CODE39 (alphanumeric), "interleaved 2 of 5" (numeric), Codabar
(numeric plus a few symbols), MSI (numeric) and Plessey (hex
digits). *Note Supported Encodings::.
`BARCODE_ANY'
This special encoding type (represented by a value of zero, so it
will be the default) tells the encoding procedure to look for the
first encoding type that can deal with a textual string.
Therefore, a 11-digit code will be printed as UPC (as well as
6-digit, 11+2 and 11+5), a 12-digit (or 7-digit, or 12+2 or 12+5)
as EAN13, an ISBN code (with or without hyphens, with or without
add-5) will be encoded in its EAN13 representation, an even number
of digits is encoded using CODE128C and a generic string is
encoded using CODE128B. Since code-39 offers a much larger
representation for the same text string, code128-b is preferred
over code39 for alphanumeric strings.
`BARCODE_NO_ASCII'
Instructs the engine not to print the ascii string on output. By
default the bar code is accompanied with an ascii version of the
text it encodes.
`BARCODE_NO_CHECKSUM'
Instructs the engine not to add the checksum character to the
output. Not all the encoding types can drop the checksum; those
where the checksum is mandatory (like EAN and UPC) just ignore the
flag.
`BARCODE_OUTPUT_MASK'
The mask is used to extract the output-type identifier from the
flags field.
`BARCODE_OUT_PS'
`BARCODE_OUT_EPS'
`BARCODE_OUT_PCL'
`BARCODE_OUT_PCL_III'
The currently supported encoding types: full-page postscript and
encapsulated postscript; PCL (print command language, for HP
printers) and PCL-III (same as PCL, but uses a font not available
on older printers).
`BARCODE_OUT_NOHEADERS'
The flag instructs the printing engine not to print the header and
footer part of the file. This makes sense for the postscript
engine but might not make sense for other engines; such other
engines will silently ignore the flag just like the PCL back-end
does.
File: barcode.info, Node: The API, Next: The barcode Executable, Prev: Supported Flags, Up: Top
Functions Exported by the Library
*********************************
The functions included in the barcode library are declared in the
header file barcode.h. They perform the following tasks:
`struct Barcode_Item *Barcode_Create(char *text);'
The function creates a new barcode object to deal with a specified
text string. It returns NULL in case of failure and a pointer to
a barcode data structure in case of success.
`int Barcode_Delete(struct Barcode_Item *bc);'
Destroy a barcode object. Always returns 0 (success)
`int Barcode_Encode(struct Barcode_Item *bc, int flags);'
Encode the text included in the bc object. Valid flags are the
encoding type (other flags are ignored) and BARCODE_NO_CHECKSUM
(other flags are silently ignored); if the flag argument is zero,
bc->flags will apply. The function returns 0 on success and -1 in
case of error. After successful termination the data structure
will host the description of the bar code and its textual
representation, after a failure the error field will include the
reason of the failure.
`int Barcode_Print(struct Barcode_Item *bc, FILE *f, int flags);'
Print the bar code described by bc to the specified file. Valid
flags are the output type, BARCODE_NO_ASCII and
BARCODE_OUT_NOHEADERS, other flags are ignored. If any of these
flags is zero, it will be inherited from bc->flags which therefore
takes precedence. The function returns 0 on success and -1 in case
of error (with bc->error set accordingly). In case of success, the
bar code is printed to the specified file, which won't be closed
after use.
`int Barcode_Position(struct Barcode_Item *bc, int wid, int hei, int xoff, int yoff, double scalef);'
The function is a shortcut to assign values to the data structure.
`int Barcode_Encode_and_Print(char *text, FILE *f, int wid, int hei, int xoff, int yoff, int flags);'
The function deals with the whole life of the barcode object by
calling the other functions; it uses all the specified flags.
`int Barcode_Version(char *versionname);'
Returns the current version as an integer number of the form major
* 10000 + minor * 100 + release. Therefore, version 1.03.5 will be
returned as 10305 and version 0.53 as 5300. If the argument is
non-null, it will be used to return the version number as a
string. Note that the same information is available from two
preprocessor macros: BARCODE_VERSION (the string) and
BARCODE_VERSION_INT (the integer number).
File: barcode.info, Node: The barcode Executable, Next: Supported Encodings, Prev: The API, Up: Top
The barcode frontend program
****************************
The barcode program is a front-end to access some features of the
library from the command line. It is able to read user supplied
strings from the command line or a data file (standard input by default)
and encode all of them.
* Menu:
* The Command Line::
File: barcode.info, Node: The Command Line, Prev: The barcode Executable, Up: The barcode Executable
The Command Line
================
barcode accepts the following options:
`--help or -h'
Print a usage summary and exit.
`-i filename'
Identify a file where strings to be encoded are read from. If
missing (and if -b is not used) it defaults to standard input.
Each data line of the input file will be used to create one
barcode output.
`-o filename'
Output file. It defaults to standard output.
`-b string'
Specify a single "barcode" string to be encoded. The option can
be used multiple times in order to encode multiple strings (this
will result in multi-page postscript output or a table of barcodes
if -t is specified). The strings must match the encoding chosen;
if it doesn't match the program will print a warning to stderr and
generate "blank" output (although not zero-length). Please note
that a string including spaces or other special characters must be
properly quoted.
`-e encoding'
encoding is the name of the chosen encoding format being used. It
defaults to the value of the environment variable BARCODE_ENCODING
or to auto detection if the environment is also unset.
`-g geometry'
The geometry argument is of the form "[<width> x <height>] [+
<xmargin> + <ymargin>]" (with no intervening spaces). Unspecified
margin values will result in no margin; unspecified size results
in default size. The specified values represent print points by
default, and can be inches, millimeters or other units according
to the -u option or the BARCODE_UNIT environment variable. The
argument is used to place the printout code on the page. Note that
an additional white margin of 10 points is added to the printout.
If the option is unspecified, BARCODE_GEOMETRY is looked up in the
environment, if missing a default size and no margin (but the
default 10 points) are used.
`-t table-geometry'
Used to print several barcodes to a single page, this option is
meant to be used to print stickers. The argument is of the form
"<columns> x <lines> [+ <leftmargin> + <bottommargin> [-
<rightmargin> [- <topmargin>]]]" (with no intervening spaces); if
missing, the top and right margin will default to be the same as
the bottom and left margin. The margins are specified in print
points or in the chosen unit (see -u below). If the option is not
specified, BARCODE_TABLE is looked up in the environment,
otherwise no table is printed and each barcode will get its own
page. The size (but not the position) of a barcode item within a
table can also be selected using -g (see "geometry" above),
without struggling with external and internal margins. I still
think management of geometries in a table is suboptimal, but I
can't make it better without introducing incompatibilities.
`-m margin(s)'
Specifies an internal margin for each sticker in the table. The
argument is of the form "<xmargin>,<ymargin>" and the margin is
applied symmetrically to the sticker. If unspecified, the
environment variable BARCODE_MARGIN is used or a default internal
margin of 10 points is used.
`-n'
"Numeric" output: don't print the ASCII form of the code, only the
bars.
`-c'
No checksum character (for encodings that allow it, like code 39,
other codes, like UPC or EAN, ignore this option).
`-E'
Encapsulated postscript (default is normal postscript). When the
output is generated as EPS only one barcode is encoded.
`-P'
PCL output. Please note that the Y direction goes from top to
bottom for PCL, and the origin for an image is the top-left corner
instead of the bottom-left
`-p pagesize'
Specify a non-default page size. The page size can be specified in
millimeters, inches or plain numbers (for example: "210x297mm",
"8.5x11in", "595x842"). A page specification as numbers will be
interpreted according to the current unit specification (see -u
below). If libpaper is available, you can also specify the page
size with its name, like "A3" or "letter" (libpaper is a standard
component of Debian GNU/Linux, but may be missing elsewhere). The
default page size is your system-wide default if libpaper is
there, A4 otherwise.
`-u unit'
Choose the unit used in size specifications. Accepted values are
"mm", "cm", "in" and "pt". By default, the program will check
BARCODE_UNIT in the environment, and assume points otherwise (this
behaviour is compatible with 0.92 and previous versions. If -u
appears more than once, each instance will modified the behaviour
for the arguments at its right, as the command line is processes
left to right. The program internally works with points, and any
size is approximated to the nearest multiple of one point. The -u
option affect -g (geometry), -t (table) and -p (page size).
File: barcode.info, Node: Supported Encodings, Next: PCL Output, Prev: The barcode Executable, Up: Top
Supported Encodings
*******************
The program encodes text strings passed either on the command line
(with -b) or retrieved from standard input. The text representation is
interpreted according to the following rules. When auto-detection of
the encoding is enabled (i.e, no explicit encoding type is specified),
the encoding types are scanned to find one that can digest the text
string. The following list of supported types is sorted in the same
order the library uses when auto-detecting a suitable encoding for a
string.
EAN
The EAN frontend is similar to UPC; it accepts strings of digits,
12 or 7 characters long. Strings of 13 or 8 characters are
accepted if the provided checksum digit is correct. I expect most
users to feed input without a checksum, though. The add-2 and
add-5 extension are accepted for both the EAN-13 and the EAN-8
encodings. The following are example of valid input strings:
"123456789012" (EAN-13), "1234567890128" (EAN-13 wih checksum),
"1234567" (EAN-8), "12345670 12345" (EAN-8 with checksum and
add-5), "123456789012 12" (EAN-13 with add-2), "123456789012
12345" (EAN-13 with add-5).
UPC
The UPC frontend accepts only strings made up of digits (and, if a
supplemental encoding is used, a blank to separate it). It
accepts strings of 11 or 12 digits (UPC-A) and 6 or 7 or 8 digits
(UPC-E).
The 12th digit of UPC-A is the checksum and is added by the
library if not specified in the input; if it is specified, it must
be the right checksum or the code is rejected as invalid. For
UPC-E, 6 digit are considered to be the middle part of the code, a
leading 0 is assumed and the checksum is added; 7 digits are
either considered the initial part (leading digit 0 or 1, checksum
missing) or the final part (checksum specified, leading 0
assumed); 8 digits are considered to be the complete code, with
leading 0 or 1 and checksum. For both UPC-A and UPC-E, a trailing
string of 2 digits or 5 digits is accepted as well. Therefore, the
following are examples of valid strings that can be encoded as UPC:
"01234567890" (UPC-A) "012345678905" (UPC-A with checksum),
"012345" (UPC-E), "01234567890 12" (UPC-A, add-2) and "01234567890
12345" (UPC-A, add-5), "0123456 12" (UPC-E, add-2). Please note
that when setting BARCODE_ANY to auto-detect the encoding to be
used, 12-digit strings and 7-digit strings will always be
identified as EAN. This because I expect most user to provide
input without a checksum. If you need to specify UPC-with-checksum
as input you must explicitly set BARCODE_UPC as a flag or use -e
upc on the command line.
ISBN
ISBN numbers are encoded as EAN-13 symbols, with an optional add-5
trailer. The ISBN frontend of the library accepts real ISBN
numbers and deals with any hyphen and, if present, the ISBN
checksum character before encoding data. Valid representations for
ISBN strings are for example: "1-56592-292-1", "3-89721-122-X" and
"3-89721-122-X 06900".
CODE 128-B
This encoding can represent all of the printing ASCII characters,
from the space (32) to DEL (127). The checksum digit is mandatory
in this encoding.
CODE 128-C
The "C" variation of Code-128 uses Code-128 symbols to represent
two digits at a time (Code-128 is made up of 104 symbols whose
interpretation is controlled by the start symbol being used). Code
128-C is thus the most compact way to represent any even number of
digits. The encoder refuses to deal with an odd number of digits
because the caller is expected to provide proper padding to an
even number of digits. (Since Code-128 includes control symbols to
switch charset, it is theoretically possible to represent the odd
digit as a Code 128-A or 128-B symbol, but this tool doesn't
currently implement this option).
CODE 128 RAW
Code-128 output represented symbol-by-symbol in the input string.
To override part of the problems outlined below in specifying
code128 symbols, this pseudo-encoding allows the used to specify a
list of code128 symbols separated by spaces. Each symbol is
represented by a number in the range 0-105. The list should
include the leading character.The checksum and the stop character
are automatically added by the library. Most likely this
pseudo-encoding will be used with BARCODE_NO_ASCII and some
external program to supply the printed text.
CODE 39
The code-39 standard can encode uppercase letters, digits, the
blank space, plus, minus, dot, star, dollar, slash, percent. Any
string that is only composed of such characters is accepted by the
code-39 encoder. To avoid loosing information, the encoder refuses
to encode mixed-case strings (a lowercase string is nonetheless
accepted as a shortcut, but is encoded as uppercase).
INTERLEAVED 2 OF 5
This encoding can only represent an even number of digits (odd
digits are represented by bars, and even digits by the
interleaving spaces). The name stresses the fact that two of the
five items (bars or spaces) allocated to each symbol are wide,
while the rest are narrow. The checksum digit is optional (can be
disabled via BARCODE_NO_CHECKSUM). Since the number of digits,
including the checksum, must be even, a leading zero is inserted
in the string being encoded if needed (this is specifically stated
in the specs I have access to).
CODE 128
Automatic selection between alphabet A, B and C of the Code-128
standard. This encoding can represent all ASCII symbols, from 0
(NUL) to 127 (DEL), as well as four special symbols, named F1, F2,
F3, F4. The set of symbols available in this encoding is not
easily represented as input to the barcode library, so the
following convention is used. In the input string, which is a
C-language null-terminated string, the NUL char is represented by
the value 128 (0x80, 0200) and the F1-F4 characters are
represented by the values 193-196 (0xc1-0xc4, 0301-0304). The
values have been chosen to ease their representation as escape
sequences.
Since the shell doesn't seem to interpret escape sequences on the
command line, the "-b" option cannot be easily used to designate
the strings to be encoded. As a workaround you can resort to the
command echo, either within back-ticks or used separately to
create a file that is then fed to the standard-input of barcode -
assuming your echo command processes escape sequences. The
newline character is especially though to encode (but not
impossible unless you use a csh variant.
These problems only apply to the command-line tool; the use of
library functions doesn't give any problem. In needed, you can use
the "code 128 raw" pseudo-encoding to represent code128 symbols by
their numerical value. This encoding is used late in the
auto-selection mechanism because (almost) any input string can be
represented using code128.
CODABAR
Codabar can encode the ten digits and a few special symbols
(minus, plus, dollar, colon, bar, dot). The characters "A", "B",
"C" and "D" are used to represent four different start/stop
characters. The input string to the barcode library can include
the start and stop characters or not include them (in which case
"A" is used as start and "B" as stop). Start and stop characters
in the input string can be either all lowercase or all uppercase
and are always printed as uppercase.
PLESSEY
Plessey barcodes can encode all the hexadecimal digits. Alphabetic
digits in the input string must either be all lowercase or all
uppercase. The output text is always uppercase.
MSI
MSI can only encode the decimal digits. While the standard
specifies either one or two check digits, the current
implementation in this library only generates one check digit.
CODE 93
The code-93 standard can natively encode 48 different characters,
including uppercase letters, digits, the blank space, plus, minus,
dot, star, dollar, slash, percent, as well as five special
characters: a start/stop delimiter and four "shift characters"
used for extended encoding. Using this "extended encoding"
method, any standard 7-bit ASCII character can be encoded, but it
takes up two symbol lengths in barcode if the character is not
natively supported (one of the 48). The encoder here fully
implements the code 93 encoding standard. Any characters natively
supported (A-Z, 0-9, ".+-/$&%") will be encoded as such - for any
other characters (such as lower case letters, brackets,
parentheses, etc.), the encoder will revert to extended encoding.
As a note, the option to exclude the checksum will eliminate the
two modulo-47 checksums (called C and K) from the barcode, but this
probably will make it unreadable by 99% of all scanning systems.
These checksums are specified to be used at the firmware level,
and their absence will be interpreted as an invalid barcode.
File: barcode.info, Node: PCL Output, Next: Bugs and Pending Issues, Prev: Supported Encodings, Up: Top
PCL Output
**********
While the default output is Postscript (possibly EPS), and Postscript
can be post-processed to almost anything, it is sometimes desirable to
create output directly usable by the specific printer at hand. PCL is
currently supported as an output format for this reason. Please note
that the Y coordinate for PCL goes from top to bottom, while for
Postscript it goes from bottom to top. Consistently, while in
Postscript you specify the bottom-left corner as origin, for PCL you
specify the top-left corner.
Barcode output for PCL Printers (HP LaserJet and compatibles), was
developed using PCL5 Reference manuals from HP. that really refers to
these printers:
* LaserJet III, III P, III D, III Si,
* LaserJet 4 family
* LaserJet 5 family
* LaserJet 6 family
* Color LaserJet
* DeskJet 1200 and 1600.
However, barcode printing uses a very small subset of PCL, probably
also LaserJet II should print it without problem, but the resulting
text may be horrible.
The only real difference from one printer to another really depends
on which font are available in the printer, used in printing the label
associated to the bars (if requested).
Earlier LaserJet supports only bitmaps fonts, so these are not
"scalable". (Ljet II ?), Also these fonts, when available, have a
specified direction, and not all of them are available in both Portrait
and Landscape mode.
From LaserJet 4 series, (except 4L/5L that are entry-level printers),
Arial scalable font should be available, so it's the "default font"
used by this program.
LaserJet III series printers (and 4L, 5L), don't feature "Arial" as a
resident font, so you should use BARCODE_OUT_PCL_III instead of
BARCODE_OUT_PCL., and font the font used will be "Univers" instead of
"Arial".
Results on compatible printers, may depend on consistency of PCL5
compatibility, in doubt, try BARCODE_OUT_PCL_III
PJL commands are not used here, as it's not very compatible.
Tested Printers:
* Hp LaserJet 4050
* Hp LaserJet 2100
* Epson N-1200 emul PCL
* Toshiba DP2570 (copier) + PCL option
* Epson EPL-7100 emul. HP LaserJet II: bars print fine but text is
bad.
File: barcode.info, Node: Bugs and Pending Issues, Prev: PCL Output, Up: Top
Bugs and Pending Issues.
************************
The current management of borders/margins is far from optimal. The
"default" margin applied by the library interferes with the external
representation, but I feel it is mandatory to avoid creating barcode
output with no surrounding white space (the problem is especially
relevant for EPS output).
EAN-128 is not (yet) supported. I plan to implement it pretty soon
and then bless the package as version 1.0.
Tag Table:
Node: Top154
Node: Overview526
Node: The Barcode Object1404
Node: The Field List2821
Node: The Intermediate Representation6586
Node: Supported Flags8359
Node: The API11343
Node: The barcode Executable14029
Node: The Command Line14458
Node: Supported Encodings19557
Node: PCL Output28997
Node: Bugs and Pending Issues31316
End Tag Table
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