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pg(1)

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terminfo(4)



     pg(1)                      DG/UX 4.30                       pg(1)



     NAME
          pg - file perusal filter for CRT terminals in DG/UX

     SYNOPSIS
          pg [-number] [-p string] [-cefns] [+linenumber] [+/pattern/]
          [files...]

     DESCRIPTION
          The pg command is a filter which allows the examination of
          files one screenful at a time on a CRT terminal.  (The file
          name - and/or NULL arguments indicate that pg should read
          from the standard input.)  Each screenful is followed by a
          prompt.  If the user types a carriage return, another page
          is displayed; other possibilities are enumerated below.

          This command is different from previous paginators in that
          it allows you to back up and review something that has
          already passed.  The method for doing this is explained
          below.

          In order to determine terminal attributes, pg scans the
          terminfo(4) data base for the terminal type specified by the
          environment variable TERM.  If TERM is not defined, the
          terminal type dumb is assumed.

          The command line options are:

          -number
               An integer specifying the size (in lines) of the window
               that pg is to use instead of the default.  (On a
               terminal containing 24 lines, the default window size
               is 23).

          -p string
               Causes pg to use string as the prompt.  If the prompt
               string contains a ``%d'', the first occurrence of
               ``%d'' in the prompt will be replaced by the current
               page number when the prompt is issued.  The default
               prompt string is ``:''.

          -c   Home the cursor and clear the screen before displaying
               each page.  This option is ignored if clearscreen is
               not defined for your terminal type in the terminfo(4)
               data base.

          -e   Causes pg not to pause at the end of each file.

          -f   Normally, pg splits lines longer than the screen width,
               but some sequences of characters in the text being
               displayed (e.g., escape sequences for underlining)
               generate undesirable results.  The -f option inhibits
               pg from splitting lines.



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     pg(1)                      DG/UX 4.30                       pg(1)



          -n   Normally, commands must be terminated by a <newline>
               character.  This option causes an automatic end of
               command as soon as a command letter is entered.

          -s   Causes pg to print all messages and prompts in standout
               mode (usually reverse video).

          +linenumber
               Start up at linenumber.

          +/pattern/
               Start up at the first line containing the regular
               expression pattern.

          The responses that may be typed when pg pauses can be
          divided into three categories: those causing further
          perusal, those that search, and those that modify the
          perusal environment.

          Commands which cause further perusal normally take a
          preceding address, an optionally signed number indicating
          the point from which further text should be displayed.  This
          address is interpreted in either pages or lines depending on
          the command.  A signed address specifies a point relative to
          the current page or line, and an unsigned address specifies
          an address relative to the beginning of the file.  Each
          command has a default address that is used if none is
          provided; it is shown in parentheses below. Control
          characters are indicated with a caret, e.g., ^c for
          <Control-C> .

          The perusal commands and their defaults are as follows:

          (+1)<newline> or <space>
               This causes one page to be displayed.  The address is
               specified in pages.

          (+1) l
               With a relative address this causes pg to simulate
               scrolling the screen, forward or backward, the number
               of lines specified.  With an absolute address this
               command prints a screenful beginning at the specified
               line.

          (+1) d or ^D
               Simulates scrolling half a screen forward or backward.

          The following perusal commands take no address.

          . or ^L
               Typing a single period causes the current page of text
               to be redisplayed.



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     pg(1)                      DG/UX 4.30                       pg(1)



          $    Displays the last windowful in the file.  Use with
               caution when the input is a pipe because pg will wait
               until the process writing to the pipe is completely
               finished before displaying anything.

          The following commands are available for searching for text
          patterns in the text.  The regular expressions described in
          ed(1) are available.  They must always be terminated by a
          <newline>, even if the -n option is specified.

          [i]/pattern/
               Search forward for the ith (default i=1) occurrence of
               pattern.  Searching begins immediately after the
               current page and continues to the end of the current
               file, without wrap-around.

          [i]^pattern^
          [i]?pattern?
               Search backwards for the ith (default i=1) occurrence
               of pattern.  Searching begins immediately before the
               current page and continues to the beginning of the
               current file, without wrap-around.  The ^ notation is
               useful for Adds 100 terminals which will not properly
               handle the ?.

          After searching, pg will normally display a screen of text
          with the found line at the top of the screen.  This can be
          modified by appending m or b to the search command to
          position the found line in the middle or at the bottom of
          the window from now on.  The suffix t can be used to restore
          the original situation.

          The user of pg can modify the environment of perusal with
          the following commands:

          [i]n Begin perusing the ith next file in the command line.
               The i is an unsigned number, and its default value is
               1.

          [i]p Begin perusing the ith previous file in the command
               line. The prompt reads Next File.  The i is an unsigned
               number, and its default is 1.

          [i]w Display another window of text.  If i is present, set
               the window size to i.  (The actual size will be i-1).

          s filename
               Save the input in the named file.  Only the current
               file being perused is saved.  The white space between
               the s and filename is optional.  This command must
               always be terminated by a <newline>, even if the -n
               option is specified.



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     pg(1)                      DG/UX 4.30                       pg(1)



          h    Provide help by displaying an abbreviated summary of
               available commands.

          q or Q
               Quit pg.

          !command
               Command is passed to the shell, whose name is taken
               from the SHELL environment variable.  If this is not
               available, the default shell /bin/sh is used.  This
               command must always be terminated by a <newline>, even
               if the -n option is specified.

          At any time when output is being sent to the terminal, the
          user can type the quit key (normally control-\) or the
          interrupt (break) key to interrupt the display.  This causes
          pg to stop sending output and display the prompt.  The user
          may then enter one of the above commands in the normal
          manner.  Unfortunately, some output is lost when this is
          done, due to the fact that any characters waiting in the
          terminal's output queue are flushed when the quit signal
          occurs.

          If the standard output is not a tty device, then pg acts
          just like cat(1), except that a header is printed before
          each file if there is more than one.

     EXAMPLE
          A sample usage of pg in reading system news would be

                              news | pg -p "(Page %d):"

     NOTES
          While waiting for terminal input, pg responds to interrupt
          and quit characters by terminating execution.  Between
          prompts, however, these signals interrupt pg's current task
          and place the user in prompt mode.  These should be used
          with caution when input is being read from a pipe, since an
          interrupt is likely to terminate the other commands in the
          pipeline.

          Users of more(1) will find that the z and f commands are
          available, and that the terminating /, ^, or ? character may
          be omitted from the searching commands.

     FILES
          /usr/lib/terminfo/?/*
                              Terminal information data base

          /tmp/pg*            Temporary file when input is from a pipe

     SEE ALSO



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     pg(1)                      DG/UX 4.30                       pg(1)



          crypt(1), ed(1), more(1), cat(1).
          terminfo(4) in the Programmer's Reference for the DG/UX
          System

     BUGS
          If terminal tabs are not set every eight positions,
          undesirable results may occur.

          When using pg as a filter with another command that changes
          the terminal I/O options (e.g., crypt(1)), terminal settings
          may not be restored correctly.












































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Typewritten Software • bear@typewritten.org • Edmonds, WA 98026