scan.man

早期freebsd实现

SCAN(1)                BSD Reference Manual               SCAN(1)


NNAAMMEE
       scan - produce a one line per message scan listing

SSYYNNOOPPSSIISS
       scan  [+folder]  [msgs] [-clear] [-noclear] [-form format-
            file]    [-format string]    [-header]    [-noheader]
            [-width columns] [-reverse] [-noreverse] [-file file-
            name] [-help]

DDEESSCCRRIIPPTTIIOONN
       _S_c_a_n produces a one-line-per-message listing of the speci-
       fied messages.  Each _s_c_a_n line contains the message number
       (name), the date, the "From:" field, the "Subject"  field,
       and, if room allows, some of the body of the message.  For
       example:

            15+  7/ 5  Dcrocker  nned  Last week I asked some of
            16 - 7/ 5  dcrocker  message id format  I recommend
            18   7/ 6  Obrien    Re: Exit status from mkdir
            19   7/ 7  Obrien    "scan" listing format in MH

       The `+' on message 15 indicates that  it  is  the  current
       message.  The `-' on message 16 indicates that it has been
       replied to, as indicated by a  "Replied:"  component  pro-
       duced by an `-annotate' switch to the _r_e_p_l command.

       If  there  is  sufficient room left on the _s_c_a_n line after
       the subject, the line will be filled with  text  from  the
       body,  preceded by <<, and terminated by >> if the body is
       sufficiently short.  _S_c_a_n actually reads each of the spec-
       ified  messages  and  parses  them  to extract the desired
       fields.  During parsing, appropriate error  messages  will
       be  produced if there are format errors in any of the mes-
       sages.

       The `-header' switch produces a header line prior  to  the
       _s_c_a_n  listing.   Currently, the name of the folder and the
       current date and time are output (see the HHIISSTTOORRYY  section
       for more information).

       If  the  `-clear'  switch  is  used  and  _s_c_a_n_'_s output is
       directed to a terminal, then _s_c_a_n will consult  the  $$TTEERRMM
       and  $$TTEERRMMCCAAPP  envariables to determine your terminal type
       in order to find out how to  clear  the  screen  prior  to
       exiting.  If the `-clear' switch is used and _s_c_a_n_'_s output
       is not directed to a terminal (e.g., a pipe  or  a  file),
       then _s_c_a_n will send a formfeed prior to exiting.

       For example, the command:

            (scan -clear -header; show all -show pr -f) | lpr



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SCAN(1)                BSD Reference Manual               SCAN(1)


       produces a scan listing of the current folder, followed by
       a formfeed, followed by a formatted listing  of  all  mes-
       sages in the folder, one per page.  Omitting `-show pr -f'
       will cause the messages to be concatenated, separated by a
       one-line header and two blank lines.

       If  _s_c_a_n  encounters  a  message  without a "Date:" field,
       rather than leaving  that  portion  of  the  scan  listing
       blank,  the  date is filled-in with the last write date of
       the message, and post-fixed with a `*'.  This is  particu-
       larly handy for scanning a _d_r_a_f_t _f_o_l_d_e_r, as message drafts
       usually aren't allowed to have dates in them.

       To  override  the  output  format  used   by   _s_c_a_n,   the
       `-format string'  or `-form file' switches are used.  This
       permits individual  fields  of  the  scan  listing  to  be
       extracted with ease.  The string is simply a format string
       and the file is simply a format file.   See  _m_h_-_f_o_r_m_a_t (5)
       for the details.

       In  addition  to  the standard _m_h_-_f_o_r_m_a_t (5) escapes, _s_c_a_n
       also  recognizes  the   following   additional   _c_o_m_p_o_n_e_n_t
       escapes:

       _E_s_c_a_p_e    _R_e_t_u_r_n_s  _D_e_s_c_r_i_p_t_i_o_n
       body      string   the (compressed) first part of the body
       dtimenow  date     the current date
       folder    string   the name of the current folder

       Also,  if  no  date header was present in the message, the
       _f_u_n_c_t_i_o_n escapes which operate on {_d_a_t_e} will return  val-
       ues  for the date of last modification of the message file
       itself.

       _s_c_a_n will update the _M_H  context  prior  to  starting  the
       listing, so interrupting a long _s_c_a_n listing preserves the
       new context.  _M_H purists hate this idea.

FFIILLEESS
       $HOME/.mh_profile                         The user profile

PPRROOFFIILLEE CCOOMMPPOONNEENNTTSS
       Path:                To determine the user's MH directory
       Alternate-Mailboxes: To determine the user's mailboxes
       Current-Folder:      To find the default current folder

SSEEEE AALLSSOO
       inc(1), pick(1), show(1), mh-format(5)

DDEEFFAAUULLTTSS
       `+folder' defaults to the folder current



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SCAN(1)                BSD Reference Manual               SCAN(1)


       `msgs' defaults to all
       `-format' defaulted as described above
       `-noheader'
       `-width' defaulted to the width of the terminal

CCOONNTTEEXXTT
       If a folder is given, it will become the current folder.

HHIISSTTOORRYY
       Prior to using the format string mechanism, `-header' used
       to generate a heading saying what each column in the list-
       ing was.  Format strings prevent this from happening.

BBUUGGSS
       The argument to the `-format' switch must  be  interpreted
       as  a single token by the shell that invokes _s_c_a_n.  There-
       fore, one must usually place the argument to  this  switch
       inside double-quotes.
       The  value  of each _c_o_m_p_o_n_e_n_t escape is set by _s_c_a_n to the
       contents of the first message header _s_c_a_n encounters  with
       the  corresponding  component  name; any following headers
       with the same component name are ignored.

       The switch `-reverse', makes _s_c_a_n  list  the  messages  in
       reverse order; this should be considered a bug.

       The  `-file  filename'  switch allows the user to obtain a
       _s_c_a_n listing of a maildrop  file  as  produced  by  _p_a_c_k_f.
       This listing includes every message in the file.  The user
       should use _m_s_h for more selective processing of the  file.
       `-reverse' is ignored with this option.























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