flnews(1)                     flnews 1.3.0 manual                    flnews(1)




NAME

       flnews - Fast and lightweight Usenet client with GUI


SYNOPSIS

       flnews [-display [host]:display] [-geometry WxH[+X+Y]]

       flnews [-h|-v]


DESCRIPTION

       If  you don't know what Usenet is, you probably want to read this arti-
       cle first:

       https://en.wikipedia.org/wiki/Usenet

       flnews is a client with graphical user interface  that  uses  the  NNTP
       protocol defined in RFC 3977 to get Usenet news articles defined in RFC
       5536 from a server via IP network. Version 1 of the NNTP  protocol  (as
       defined  in  RFC  977)  is supported too and automatically used, if the
       server does not report support for Version 2.

       If compiled with support for ssl(3),  the  NNTPS  protocol  (NNTP  over
       encrypted  TLS  connection)  is  supported.  For  NNTPS connections the
       server to client authentication via X509  certificate  is  always  per-
       formed.  Optionally  the  client can authenticate to the server via the
       AUTHINFO USER/PASS extension defined in RFC 4643.

       If compiled with support for compression and zlib(3), the NNTP COMPRESS
       extension  is supported. Compression negotiation is disabled by default
       and can be enabled on the 'Edit->Configuration->Misc' tab in  the  user
       interface.   Because  compression in general can weaken the underlaying
       encryption, the optional authentication is always done before  compres-
       sion is negotiated.  For the same reason compression negotiation should
       be disabled for reading groups that contain articles with  confidential
       information.

       flnews  provides  full Unicode support, including NFC normalization for
       posting and search/compare operations. Article content is converted  to
       ISO  8859-1  before  posting  (if  possible) to be more friendly to old
       clients.  The ability to display Unicode content  depends  on  the  GUI
       toolkit fltk(3).  Even if the content could not be correctly displayed,
       it is always possible to correctly quote it in follow-up articles.

       flnews has MIME support according to RFC 2045, RFC 2046, RFC  2047  and
       RFC  2231.   Since  version 0.18 full MIME conformance according to RFC
       2049 Section 2 was reached.  Posted articles should be fully  RFC  5536
       conformant (without postprocessing by the user).

       Additional  checks  are  implemented that create warnings if an article
       violates common Usenet conventions. Conformance to mandatory GNKSA  2.0
       rules was reached with exception of part 4 (the "Reply-To" header field
       can only be modified before the article composer is started):

       https://gnksa.org/

       Currently flnews 1.3.0 provides no support for the following features:

       o  Multiple servers

       o  Offline mode

       o  UUCP

       If you need one of these features, use  leafnode(8)  or  another  proxy
       server (consider Hamster for machines with Windows operating system).


OPTIONS

       The following options are supported:

       -4                       Force usage of IPv4 network protocol.

       -confprefix path         Use different configuration directory (specify
                                path without trailing slash).

                                Attention: Never set path to an existing  con-
                                figuration directory for flnews with a differ-
                                ent major version number!

       -debug                   Enable debug mode.

                                Additional messages are printed to the  termi-
                                nal via stderr.

                                The network communication with the NNTP server
                                is logged.  See "logfile" in  the  FILES  sec-
                                tion.

       -display [host]:display  X display to use. More information about X can
                                be found in X(7).

       -geometry WxH[+X+Y]      Window size and position.

       -h                       Print help message.

       -iconic                  Starts with minimized window.

       -notooltips              Disable tooltip messages.

       -v                       Print version  information  and  compile  time
                                options.

                                Compile time options:

                                o  CLB (POSIX.2 C Language Binding)

                                o  FSC (POSIX.1 File Synchronization option)

                                o  IP6 (Internet Protocol V6)

                                o  NLS (National Language Support)

                                o  P2K (POSIX.1-2001 or newer)

                                o  TLS (Transport Layer Security)

                                o  XSI (X/Open System Interface extension)

                                o  ZLIB (DEFLATE compression algorithm)


EXIT STATUS

       Zero on regular exit. All other values indicate an error.


ENVIRONMENT

       DISPLAY                  X display to use. More information about X can
                                be found in X(7).

       FLTK_SCHEME              Selects the FLTK scheme  to  use.  FLTK  1.3.0
                                accepts the following options:

                                o  none (Default style)

                                o  gtk+ (GTK+ style)

                                o  plastic (Aqua style)

                                Newer  FLTK  versions  may  accept  additional
                                schemes.

       TMPDIR                   Directory used for temporary files (as  recom-
                                mended by POSIX). This value will override the
                                default "/tmp".

       TZ                       The timezone that  is  used  by  localtime(3).
                                flnews  internally  uses this function to con-
                                vert POSIX timestamps to local  time  and  for
                                creating  'date-time'  tokens according to RFC
                                5322.

       XDG_CONFIG_HOME          Prefix  for   configuration   directory   path
                                according to XDG Base Directory Specification.
                                This value will override the default  "~/.con-
                                fig".   The program name flnews is appended as
                                last path component.

       In addition, flnews honours the following locale related variables:

       LANG                     Used as fallback if  LC_*  variables  are  not
                                set.

       LC_ALL                   Overdrives all other LC_* variables.

       LC_CTYPE                 Character  classification to use. Only locales
                                with US-ASCII, ISO 8859-1 and  UTF-8  codesets
                                are  allowed  here.  Setting  this to a locale
                                with UTF-8 codeset is very expensive  on  some
                                operating  systems (e.g. more than an order of
                                magnitude slower on NetBSD 5).  Note that set-
                                ting  this  to  POSIX  or an ISO 8859-1 locale
                                will not completely disable  Unicode  support!
                                You  can at least use Unicode for your name in
                                the identity configuration and  you  can  cor-
                                rectly  quote  Unicode  content  for follow-up
                                articles in any case.

       LC_MESSAGES              Locale for user interface language. The  code-
                                set  is ignored because FLTK internally always
                                use UTF-8 (regardless of the locale settings).
                                If  flnews  is  compiled without National Lan-
                                guage Support (NLS), this variable is ignored.

       As a general rule, POSIX.2 define that all locale sections must use the
       same  codeset.  More  information  about  NLS can be found in nls(7) or
       locale(7) depending on the operating system.


X RESOURCES

       Information about X resources and how to set them can be found in X(7).

       fltk.background          (String) The value of this ressource is  taken
                                as  the background color for most widgets (see
                                Text.background if it does not work).

       fltk.foreground          (String) The value of this ressource is  taken
                                as the foreground color for most widgets.

       fltk.scheme              (String)    See   the   environment   variable
                                FLTK_SCHEME for possible values. The  environ-
                                ment   variable  takes  precedence  over  this
                                ressource.

       Text.background          (String) The value of this ressource is  taken
                                as  the  background  color for text, list, and
                                valuator widgets.

       Text.selectBackground    (String) The value of this ressource is  taken
                                as  the  background  color  for selected text.
                                Set it to something like  "gray"  for  a  more
                                decent  selection  color.   On  machines  with
                                8-bit color  depth  the  highlight  color  for
                                search  results  (that  is  derived  from  the
                                selection background color) may have little or
                                no  contrast. Use a darker color in this case,
                                e.g. "darkgray".

       Xft.antialias            (Boolean) If FLTK uses the X11 backend and  is
                                compiled  to  use  Xft (the default), then the
                                value "true" will enable and "false" will dis-
                                able font anti-aliasing.  The recommended set-
                                ting is "true".

       Xft.hinting              (Boolean) If FLTK uses the X11 backend and  is
                                compiled  to  use  Xft (the default), then the
                                value "true" will enable and "false" will dis-
                                able font hinting.  The recommended setting is
                                "true".

       Xft.autohint             (Boolean) If FLTK uses  the  X11  backend,  is
                                compiled  to  use Xft (the default) and Xft is
                                configured with enabled font hinting (resource
                                Xft.hinting  set to "true") then this resource
                                controls the hinting algorithm.  With  setting
                                "false"  the  BCI  algorithm  is  used, "true"
                                enables the builtin autohinter  of  Freetype2.
                                The recommended setting is "false".

       Xft.hintstyle            (Integer)  If  FLTK  uses  the X11 backend, is
                                compiled to use Xft (the default) and  Xft  is
                                configured with enabled font hinting (resource
                                Xft.hinting set to "true") then this  resource
                                controls the hinting mode. Possible values are
                                "hintnone" (0), "hintslight" (1), "hintmedium"
                                (2)  and "hintfull" (3).  The recommended set-
                                ting is "hintfull" (3).

                                Attention: With some modes it is possible that
                                lines  will overlap and characters like under-
                                score are clipped!


FILES

       ~/.signature             The signature from this file is  automatically
                                appended to all created articles.
                                This  file is not used if another location for
                                the signature file is configured.  See CONFIG-
                                URATION  section below for details (configfile
                                entry "signature_file").

                                Note:  At  this  (shared)  location  the  file
                                should be US-ASCII encoded. If you want to use
                                Unicode in signatures, a  dedicated  signature
                                file for flnews should be configured.

       The following files are inside the configuration directory. The default
       location  is  "~/.config/flnews".  The  environment  variable  XDG_CON-
       FIG_HOME and the option -confprefix (highest precedence) can be used to
       modify the configuration directory location.

       .cancelsecret            Secret for generating Cancel-Locks/-Keys  with
                                scheme SHA256 according to RFC 8315.
                                The secret in this file must be a cryptograph-
                                ically random value according to RFC 4086  and
                                should be at least 32 octets in length.

                                flnews  must  be  compiled  with  support  for
                                ssl(3) or this file will be  ignored,  because
                                the cryptographic functions are shared.

                                If  this  file is not present, it is automati-
                                cally created and a new secret is  written  to
                                it  (using  random data from the cryptographic
                                PRNG).

                                If this file is present and not empty, and the
                                fqdn  entry  is  set,  flnews creates "Cancel-
                                Lock" (always) and "Cancel-Key" header  fields
                                when canceling or superseding articles.

                                To use the same secret as another installation
                                of flnews (or another newsreader that use  the
                                algorithm  recommended  by  RFC 8315 with HMAC
                                based on  SHA256),  copy  the  file  with  the
                                desired secret to this location.

                                To  manually  disable  this  feature, an empty
                                file must be used.

                                Attention: Everybody who get his hands on this
                                secret  can  cancel  articles that were locked
                                using this key in the past! This  file  should
                                be readable only by the user.

                                The  old  scheme  SHA1 is still supported too.
                                See CONFIGURATION section  below  for  details
                                (configfile entry "cancelkey").

       configfile               Configuration and user interface state of last
                                session. The file format is forward and  back-
                                ward compatible between all versions with same
                                major number.

                                See CONFIGURATION section below for details.

       groupfile                Subscribed groups and already viewed  articles
                                database.  The  data  is  US-ASCII  encoded in
                                newsrc format and can  be  shared  with  other
                                newsreaders  using the entry newsrc in config-
                                file. It is possible to share the  group  data
                                over  machine  borders  by  using a NFS server
                                (advisory file locking support is required).

                                Attention: In any case  all  newsreaders  that
                                share  a  groupfile  must be configured to use
                                the same server! There is a convention to name
                                such files "newsrc-$HOSTNAME" to make it obvi-
                                ous for which server they can be used.

                                It is allowed to share the  groupfile  between
                                multiple instances of flnews that run simulta-
                                neously. The file will contain  the  state  of
                                the instance that is terminated last.

       headers/*                Cached article header database. The file names
                                correspond to the article  watermarks  of  the
                                current  NNTP  server.  If the server provides
                                the OVER capability defined in RFC 3977,  this
                                database is not used.

                                Overview usage can be explicitly disabled. See
                                CONFIGURATION section below for details  (con-
                                figfile entry "nntp_no_over").

       logfile                  Protocol  dump  of  server  communication from
                                current/last session. To view this data  while
                                the  program is running, select 'Tools->Proto-
                                col console' in the user interface. This  file
                                is overwritten for every new connection.

                                Only  enabled  in  debug mode. See "-debug" in
                                the OPTIONS section.

       scorefile                Scoring rules. The file format is forward  and
                                backward  compatible between all versions with
                                same major number.  The  data  can  be  shared
                                using  the  entry scorerc in configfile. It is
                                possible  to  share  the  scoring  rules  over
                                machine  borders  by using a NFS server (advi-
                                sory file locking support is required).

                                It is allowed to share the  scorefile  between
                                multiple instances of flnews that run simulta-
                                neously. The file will contain  the  state  of
                                the instance that is terminated last.

                                See SCORING section below for details.


CONFIGURATION

       This section describes the format of the configfile.

       This  file must be a POSIX textfile, this means every line must be ter-
       minated with a LF line break.

       Any line starting with '#' is treated as  a  comment  (not  parsed  and
       ignored).  Missing entries are automatically added, unsupported entries
       are ignored.

       The content can have one of  two  types:  Integer  or  Unicode  string.
       Strings use the UTF-8 representation and NFC normalization of Unicode.

       The  following entries are supported by version 1.3.0 but can't be con-
       figured from the GUI. Some have no GUI editor by intent. If  you  don't
       know what you are doing, consider to not modify them.

       o  cancelkey  (String)  Secret  for  generating Cancel-Locks/-Keys with
          scheme SHA1 according to RFC 8315

          flnews must be compiled with support for ssl(3) to make  this  work,
          because the cryptographic functions are shared.

          If  this  entry  and the fqdn entry are set, flnews creates "Cancel-
          Lock" (always) and "Cancel-Key"  header  fields  when  canceling  or
          superseding articles.

          Note: The scheme SHA1 is obsolete since RFC 8315. This entry is pre-
          served for backward compatibility. After a  transition  period  this
          entry should be left empty and the scheme SHA256 should be used. See
          section above (File "~/.config/flnews/.cancelsecret").

       o  color_xxx (Integer) Text foreground color for xxx.

          The value must be an 8-bit index for the FLTK colormap:

          https://www.fltk.org/doc-1.3/drawing.html#drawing_colors

       o  crl_check (Integer) Enable TLS certificate CRL checks

          A nonzero value means that CRL checks are enabled.

          flnews must be compiled with support for CRL  checks  to  make  this
          work.

       o  crl_upd_c (Integer) TLS certificate CRL update choice

          A  nonzero  value  means  that,  after  the  CRL update interval has
          elapsed, the user get a choice to  select  whether  the  CRL  update
          should be delayed.

       o  crl_upd_iv (Integer) TLS certificate CRL update interval

          The  value  must  be  positive and is a period of time in hours. Too
          large values (longer than one year) are clamped to the upper  limit.
          The  value  zero  means that new CRLs should be downloaded for every
          new connection (not recommended).

       o  crl_upd_ts (String) TLS certificate CRL update timestamp

          This entry contains a timestamp in ISO 8601 format for the last suc-
          cessful CRL update.

       o  dist_suggestions (Integer) Use distribution suggestions

          Setting this to a nonzero value automatically initialize the distri-
          bution header field in the composer with suggested distribution data
          (if  available).   If  no distribution suggestions are available for
          the target groups, the header field is  initialized  to  "world"  as
          with this option set to zero.

          Any  time  a  distribution  suggestion is used, the user is informed
          with a popup window in the GUI.

          With the NNTP protocol the command  LIST  DISTRIB.PATS  is  used  to
          retrieve the distribution suggestions from the server.

       o  editor (String) Optional external editor for article composition

          The pathname of an executable program must be specified.

          The  pathname  of a file containing the data is passed as parameter.
          If the external  editor  requires  additional  parameters,  a  start
          script  must be specified (and the script must provide the additonal
          parameters).

          The editor must be able to process Unicode  data  in  UTF-8  format.
          The  specified  editor  must terminate with exit status zero on suc-
          cess.

          A temporary file is used. Consider to  set  the  TMPDIR  environment
          variable.

       o  flowed_insert_crlf (Integer) Add empty line after paragraph

          Only used if "Format=flowed" is declared.

          A value of zero corresponds to the dumb behaviour up to version 0.16
          (if a paragraph ends with an empty line, there is no  separation  to
          the following text).

          A  value  of  one adds an empty line separator after every paragraph
          that ends with an empty line. This is required to create single line
          paragraphs  (allow  single line to be rewrapped to smaller width for
          display).  The author of an article can request this behaviour  with
          the  experimental  parameter  "InsLine=yes"  in  addition  to  "For-
          mat=flowed".

       o  fqdn (String) Fully qualified domain name (FQDN) of the machine

          Must be empty or a valid "dot-atom"  according  to  RFC  5322,  this
          means the nameless root domain must be omitted (no trailing dot).

          This  entry is used to generate Message-IDs. They are only worldwide
          unique for all time if flnews runs on a  machine  with  a  FQDN.  In
          addition the clock of the machine must be synchronized so that time-
          stamps are not ambigous.

          If a FQDN is configured, the header fields "Message-ID", "Injection-
          Date",  "Cancel-Lock"  and  "Cancel-Key"  (only  when  cancelling or
          superseding an article) are created by flnews for all outgoing arti-
          cles.  Note  that  RFC  5537  specifies  some  nasty details for the
          "Injection-Date" header field (they are  the  reason  to  handle  it
          internally in this case).

       o  force_unicode (Integer) Force Unicode for outgoing articles

          With the value zero outgoing articles are converted to ISO 8859-1 if
          possible.  With a nonzero value, all articles are sent using Unicode
          (UTF-8 transformation format).

       o  immedauth (Integer) Immediate authentication option

          The value one represents the default behaviour to authenticate imme-
          diately after a connection was established.

          The value  zero  switches  the  behaviour,  so  that  authentication
          against  the  server  is only executed after a request to do so (480
          response when using NNTP protocol).

       o  inews (String) Pathname of an optional external inews

          The external inews must accept the article on its standard input and
          inject  it  into  the  network.  After successful completion of this
          task it must terminate with exit status zero.  In  the  case  of  an
          error, it must terminate with a nonzero exit status.

          Note  that  the article feeded into the external inews has canonical
          format (CR+LF line breaks).

          If your inews needs command line parameters  or  a  different  input
          format,  specify  a  shell  script here (and call the external inews
          from this script).

       o  initial_greeting (String) Greeting line for  first  article  of  new
          thread

          The  content  is  automatically  inserted into the body of every new
          regular article (that is not a followup, cancel or supersede).

       o  intro (String) Introduction line format

          The name of the cited author can be inserted with "%s".   The  news-
          groups  list  of the cited article can be inserted with "%g".  Every
          variable is allowed only once.

          The last character should be a colon.

       o  inv_order (Integer) Inverse order

          The value zero is the default behaviour (top down).

          A nonzero value inverts the order of  articles  or  thread  branches
          respectively.

       o  kill_threshold (Integer) Threshold score to kill articles

          The  score  of  an  article is compared to this threshold when it is
          added to the article tree/list. Articles with  a  score  below  this
          threshold are killed (not displayed).

          The  minimum  value  is  -49999 and the maximum value is 0 (kill all
          articles with negative score).

          The value -9999 is used as default.

          The default score of an article is 0. See SCORING section below  how
          to increase or decrease the score of articles.

       o  newsrc  (String)  Optional pathname of file to share group states in
          newsrc format

          This file is imported at startup and used as groupfile. At exit  the
          local groupfile is copied back to this location. Note that this file
          is replaced with rename(2) and is not modified in place. If the file
          is accessed via NFS, advisory locking must be available.

       o  nntp_no_over  (Integer) Disable usage of overview (OVER command) for
          NNTP protocol

          Setting this to a nonzero value disables usage of overview and makes
          the whole newsgroup list usable for scoring rules.

          If  the  usage  of overview is disabled with a nonzero value (or the
          server has offered no OVER capability),  then  article  headers  are
          stored in a local database. See "headers/*" in the FILES section.

          In general the default value 0 should be used. There are two scenar-
          ios for which this option may be useful.

          If the network connection to the server is very  slow  and  no  data
          compression  is available: In this case the transfer of the (larger)
          overview may be slower than the transfer  of  a  few  (smaller)  new
          headers, because the older headers can be taken from the local data-
          base.

          If one or more scoring rules should match other (not the current  or
          not  subscribed  at all) newsgroups in Xposts: Because the newsgroup
          list is not part of the overview, only the current group  is  avail-
          able if the overview is used.

       o  organization (String) Optional name of the users organization

          The  string  is  inserted as 'Organization' header field in outgoing
          articles.

       o  post_proc (String) Pathname of an optional article postprocessor

          Note: The postprocessor can be used to insert custom header fields.

          The postprocessor must be a filter in Unix sense. It must accept the
          article  on  its  standard input, process it and write the result to
          its standard output.  After successful completion of this  task,  it
          must  terminate  with exit status zero. In the case of an error, the
          postprocessor must terminate with a nonzero exit status.

          Note that the article feeded into the  postprocessor  has  canonical
          format  (CR+LF  line  breaks) and use Unicode UTF-8 encoding for the
          body. Modifications must preserve this format.  The Unicode  normal-
          ization,  potential  conversion  to the target character set and the
          application of the transfer encoding to the body is done  after  the
          postprocessing.  Therefore  the  postprocessor is not allowed to add
          "Content-Type" and "Content-Transfer-Encoding" header fields!

          The header is already in RFC 2047 format. If the postprocessor modi-
          fies  an  existing header field, this format must be preserved. If a
          new header field is added, the postprocessor is responsible for cre-
          ating valid RFC 2047 encoding and Unicode normalization to NFC.

       o  refresh_interval (Integer) Group list refresh interval

          The value zero is the default behaviour and disables the autorefresh
          feature.

          A nonzero value refreshes the group list in the  specified  interval
          (in minutes).

       o  scorerc (String) Optional pathname of file to share scoring rules

          This  file is imported at startup and used as scorefile. At exit the
          local scorefile is copied back to this location. Note that this file
          is replaced with rename(2) and is not modified in place. If the file
          is accessed via NFS, advisory locking must be available.

       o  signature_file (String) Pathname of file with signature (relative to
          home directory)

          Default value: ".signature".

          If this file is present, its content is used as signature.  The sig-
          nature separator "dash dash space" plus LF line break  is  automati-
          cally  prepended if not already present in this file.  The file must
          be a POSIX text file (LF line break after every line, including  the
          last  one) with Unicode encoding in UTF-8 format (Unicode normaliza-
          tion is not important and applied automatically).

          Use an empty string to disable signature generation.

       o  testgrp_ere (String) POSIX.2 Extended Regular Rxpression (Unicode is
          allowed)

          If  non US-ASCII characters are used in the regular expression, they
          must be representable in the codeset of the character classification
          locale  used  at runtime. Otherwise the regular expression from this
          entry is ignored and will never match. See the  desciption  for  the
          LC_CTYPE environment variable above for details.

          Note that this regular expression is used for matching against indi-
          vidual group names, not group lists. This means  '^'  and  '$'  will
          match start and end of individual group names.

          If  a  match is detected against a group name, this group is treated
          as a test group that may require special  control  commands  in  the
          "Keywords"  header  field  to silence e.g. reflector bots (see entry
          "testgrp_kwords" for keyword configuration).

       o  testgrp_kwords (String) Comma separated list of words

          If a target group of an article is identified as a  test  group  (as
          described  for the "testgrp_ere" entry), the header field "Keywords"
          is initialized to the value defined with this entry.

          Attention: Version 1.3.0 of flnews currently only supports  US-ASCII
          keywords. Do not use spaces around commas.

       o  timestamp_comment (Integer) Generate Date header field with timezone
          comment

          The value zero represents the default behaviour to  append  no  com-
          ment.

          The  value  one  switches  the behaviour, so that a comment with the
          name of the timezone is appended to the Date header  field.  If  the
          operating  system  does not provide timezone information, this entry
          is ignored.

       o  tls_owncerts (Integer) Use local trust anchors for TLS

          With nonzero value the trust anchor (X.509 root  certificate)  of  a
          certificate chain is searched in the local location only. The system
          wide certificate store of the OpenSSL installation is ignored.

          Local X.509 certificate path: ~/.config/flnews/certs

          Copy the root certificate (in PEM format) to a file  with  arbitrary
          name  in  the path specified above. Then run the c_rehash utility to
          create the symlink that OpenSSL uses for searching.

       o  unread_in_next_group (Integer) Skip to next group for unread article

          With zero value searching for next unread article stays  in  current
          group.

          With  nonzero  value the next group with unread articles is selected
          if there are no more unread articles in the current group.


SCORING

       This section describes the format of the scorefile.

       This file must be a POSIX textfile, this means every line must be  ter-
       minated with a LF line break.

       Any  line  starting  with  '#'  is treated as a comment (not parsed and
       ignored).

       Since version 1.3.0 empty lines are ignored.  This  change  is  forward
       compatible  (older  1.x  versions create parse error messages for empty
       lines, but preserve them and handle the other lines as expected).

       All other lines are parsed as rules with four colon-separated fields:

       o  Target The groups to which the rule is associated.

          This must be a wildmat according to RFC 3977. The wildmat  "*"  will
          match all groups.

       o  Type The header field to which the rule is associated. This field is
          case sensitive.

          All types with suffix "_ere"  use  pattern  matching  with  a  POSIX
          Extended Regular Expression (ERE):

          https://pubs.open-
          group.org/onlinepubs/9699919799/basedefs/V1_chap09.html

          The following types (in alphabetical order) are recognized  by  ver-
          sion 1.3.0.

          Type  "from":  The string from the fourth field must match literally
          against the "From" header field body.

          Type "from_ere": The string from the fourth field is interpreted  as
          a POSIX.2 ERE  and must match against the "From" header field body.

          Type  "group": The string from the fourth field must match literally
          against a group element in the "Newsgroups" header field body.

          Type "msgid_ere": The string from the fourth field is interpreted as
          a  POSIX.2  ERE and must match against the "Message-ID" header field
          body.

          Type "subject": The string from the fourth field must  match  liter-
          ally against the "Subject" header field body.

          Type  "subject_ere": The string from the fourth field is interpreted
          as a POSIX.2 ERE and must match against the "Subject"  header  field
          body.

       o  Score The score value that apply if the filter rule matches.

          This  must  be  a  signed  integer value. If the scorefile is shared
          between multiple instances of flnews, the values must be usable  for
          the whole group. The machine with the smallest limits will clamp the
          values if they are too large or too small respectively.

       o  String The rules content string.

          This must always be an Unicode string (in UTF-8 format with NFC nor-
          malization).

          Attention:  If the normalization is wrong, the rule may not match as
          intended!

          The colon has no special meaning inside this field anymore and  must
          not be quoted for any of the rule types listed above.

       Note  that rules using wildmats (other than "*") and/or regular expres-
       sions are ignored if flnews is compiled  without  support  for  regular
       expressions.

       If  non US-ASCII characters are used in a regular expression, they must
       be representable in the codeset of the character classification  locale
       used  at  runtime.  Otherwise the regular expression from this entry is
       ignored and will never match. See the desciption for the LC_CTYPE envi-
       ronment variable above for details.

       The  default  score  for  every article is zero. If a rule matches, the
       score value from the second field will be added  to  the  corresponding
       article.  Note  that  the  processing is not stopped after a match, the
       following rules are applied too.

       Articles with nonzero score result are marked with icons  in  the  GUI.
       Articles with negative score result are additionally marked as read.


NOTES

       flnews is based in part on the work of the following projects:

       o  FLTK toolkit for graphical user interface (https://www.fltk.org/)

       o  Unicode standard for text encoding (https://www.unicode.org/)

          Unicode  is  a  registered  trademark of Unicode, Inc. in the United
          States and other countries.

       o  OpenSSL cryptographic libraries (https://www.openssl.org/)

          If compiled with support for TLS.

       o  LibreSSL cryptographic libraries (https://www.libressl.org/)

          If compiled with support for TLS (as replacement for OpenSSL).

       o  zlib compression library (https://zlib.net/)

          If compiled with support for compression.


AUTHORS

       To  view  the  list  of  authors  and   the   license   terms,   select
       'Help->License' in the user interface.


BUGS

       To report bugs, select 'Help->Bug report' in the user interface.


STANDARDS

       flnews tries to comply with the following standards:

       ISO  2022,  ISO  8601, ISO 8859, RFC 20, RFC 822, RFC 850, RFC 977, RFC
       1468, RFC 1738, RFC 2045, RFC 2046, RFC 2047, RFC 2049, RFC  2104,  RFC
       2152,  RFC  2183, RFC 2231, RFC 2246, RFC 2368, RFC 2585, RFC 2606, RFC
       2646, RFC 2980, RFC 3174, RFC 3629, RFC 3676, RFC 3977, RFC  3986,  RFC
       4346,  RFC  4642, RFC 4643, RFC 5198, RFC 5246, RFC 5280, RFC 5322, RFC
       5536, RFC 5537, RFC 5538, RFC 6048, RFC 6066, RFC 6068, RFC  6176,  RFC
       6657,  RFC  7230, RFC 7231, RFC 7234, RFC 7366, RFC 7507, RFC 7568, RFC
       7627, RFC 7919, RFC 8054, RFC 8089, RFC 8143, RFC 8315, RFC  8446,  RFC
       8996,    POSIX.2-1992,    POSIX.1-1996,   POSIX.1-2001,   POSIX.1-2008,
       POSIX.1-2024, Unicode 17.0.0, XDG Base Directory Specification 0.7


SEE ALSO

       fltk(3), leafnode(8), locale(7), localtime(3), nls(7), ssl(3), zlib(3),
       X(7)

       https://en.wikipedia.org/wiki/Usenet

       https://gnksa.org/

       https://pubs.open-
       group.org/onlinepubs/9799919799/basedefs/V1_chap09.html



Unix                              2026-01-27                         flnews(1)