pg - files perusal filter for CRTs
pg [-number] [-p string] [-cefnrs] [ + linenumber] [ +/ pat-
tern /] [filename...]
The pg command is a filter that allows the examination of
filenames one screenful at a time on a CRT. If the user
types a RETURN, another page is displayed; other possibili-
ties are listed 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
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.
An integer specifying the size (in lines) of the win-
dow that pg is to use instead of the default. (On a
terminal containing 24 lines, the default window size
pg uses 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
-c Home the cursor and clear the screen before displaying
each page. This option is ignored if clear_screen is
not defined for this terminal type in the terminfo(4)
-e pg does not 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 (for instance, escape sequences for
underlining) generate undesirable results. The -f
option inhibits pg from splitting lines.
-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.
-r Restricted mode. The shell escape is disallowed. pg
prints an error message but does not exit.
-s pg prints all messages and prompts in the standard
output mode (usually inverse video).
Start up at linenumber.
Start up at the first line containing the regular
The following operands are supported:
A path name of a text file to be displayed. If no
filename is given, or if it is -, the standard input
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
Commands that cause further perusal normally take a preced-
ing 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 com-
mand has a default address that is used if none is provided.
The perusal commands and their defaults are as follows:
(+1)<newline> or <blank>
This causes one page to be displayed. The address is
specified in pages.
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
(+1) d or ^D
Simulates scrolling half a screen forward or backward.
if Skip i screens of text.
iz Same as <newline> except that i, if present, becomes
the new default number of lines per screenful.
The following perusal commands take no address.
. or ^L
Typing a single period causes the current page of text
to be redisplayed.
$ Displays the last windowful in the file. Use with cau-
tion when the input is a pipe.
The following commands are available for searching for text
patterns in the text. The regular expressions are described
on the regex(5) manual page. They must always be terminated
by a <newline>, even if the -n option is specified.
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.
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 the line found at
the top of the screen. This can be modified by appending m
or b to the search command to leave the line found in the
middle or at the bottom of the window from now on. The suf-
fix t can be used to restore the original situation.
The user of pg can modify the environment of perusal with
the following commands:
in Begin perusing the ith next file in the command line.
The i is an unsigned number, default value is 1.
ip Begin perusing the ith previous file in the command
line. i is an unsigned number, default is 1.
iw Display another window of text. If i is present, set
the window size to i.
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.
h Help by displaying an abbreviated summary of available
q or Q
Command is passed to the shell, whose name is taken
from the SHELL environment variable. If this is not
available, the default shell 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 hit the quit key (normally CTRL-\) or the interrupt
(break) key. 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, because any characters waiting in
the terminal's output queue are flushed when the quit signal
If the standard output is not a terminal, then pg acts just
like cat(1), except that a header is printed before each
file (if there is more than one).
Large File Behavior
See largefile(5) for the description of the behavior of pg
when encountering files greater than or equal to 2 Gbyte ( 2
Example 1: An example of the pg command.
The following command line uses pg to read the system news:
example% news | pg -p "(Page %d):"
See environ(5) for descriptions of the following environment
variables that affect the execution of pg: LC_CTYPE,
LC_MESSAGES, and NLSPATH.
The following environment variables affect the execution of
Determine the horizontal screen size. If unset or
NULL, use the value of TERM, the window size, baud
rate, or some combination of these, to indicate the
terminal type for the screen size calculation.
LINES Determine the number of lines to be displayed on the
screen. If unset or NULL, use the value of TERM,
the window size, baud rate, or some combination of
these, to indicate the terminal type for the screen
SHELL Determine the name of the command interpreter executed
for a !command.
TERM Determine terminal attributes. Optionally attempt to
search a system-dependent database, keyed on the value
of the TERM environment variable. If no information is
available, a terminal incapable of cursor-addressable
movement is assumed.
The following exit values are returned:
0 Successful completion.
>0 An error occurred.
temporary file when input is from a pipe
terminal information database
See attributes(5) for descriptions of the following attri-
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
| Availability | SUNWcsu |
| CSI | enabled |
cat(1), grep(1), more(1), terminfo(4), attributes(5),
environ(5), largefile(5), regex(5)
While waiting for terminal input, pg responds to BREAK,
CTRL-C, and CTRL-\ 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
The terminal /, ^, or ? may be omitted from the searching
If terminal tabs are not set every eight positions, undesir-
able results may occur.
When using pg as a filter with another command that changes
the terminal I/O options, terminal settings may not be
Man(1) output converted with