NAME
pr
—
print files
SYNOPSIS
pr |
[+page]
[- column]
[-adFfmrt ] [-e
[char] [gap]]
[-h header]
[-i [char]
[gap]]
[-l lines]
[-n [char]
[width]]
[-o offset]
[-s [char]]
[-w width] [-]
[file ...] |
DESCRIPTION
The pr
utility is a printing and
pagination filter for text files. When multiple input files are specified,
each is read, formatted, and written to standard output. By default, the
input is separated into 66-line pages, each with
- A 5-line header with the page number, date, time, and the pathname of the file.
- A 5-line trailer consisting of blank lines.
Optionally, the trailer can be replaced by a
<form-feed> where this is more appropriate for the
output device being used and <tab>s can be expanded
to input relative <spaces>s or
<space>s can be contracted to output relative
<tab>s. The pr
utility also
interprets <form-feed>s in the input as the logical
end of pages.
When multiple column output is specified, text columns are of equal width. By default text columns are separated by at least one <blank>. Input lines that do not fit into a text column are truncated, except in the default single columns output mode.
If standard output is associated with a terminal, diagnostic
messages are suppressed until the pr
utility has
completed processing.
In the following option descriptions, column, lines, offset, page, and width are positive decimal integers and gap is a non-negative decimal integer.
The options are as follows:
- +page
- Begin output at page number page of the formatted input.
-
column- Produce output that is columns wide (default is 1)
that is written vertically down each column in the order in which the text
is received from the input file. The options
-e
and-i
are assumed. This option should not be used with-m
. When used with-t
, the minimum number of lines is used to display the output. -a
- Modify the effect of the
-
column option so that the columns are filled across the page in a round-robin order (e.g., when column is 2, the first input line heads column 1, the second heads column 2, the third is the second line in column 1, etc.). This option requires the use of the-
column option. -d
- Produce output that is double spaced. An extra <newline> character is output following every <newline> found in the input.
-e
[char] [gap]- Expand each input <tab> to the next greater column position specified by the formula n*gap+1, where n is an integer > 0. If gap is zero or is omitted the default is 8. All <tab> characters in the input are expanded into the appropriate number of <space>s. If any nondigit character, char, is specified, it is used as the input tab character.
-F
- Use a <form-feed> character for new pages, instead of the default behavior that uses a sequence of <newline> characters.
-f
- Same as the
-F
option. -h
header- Use the string header to replace the file name in the header line.
-i
[char] [gap]- In output, replace multiple <space>s with <tab>s whenever two or more adjacent <space>s reach column positions gap+1, 2*gap+1, etc. If gap is zero or omitted, default <tab> settings at every eighth column position is used. If any nondigit character, char, is specified, it is used as the output <tab> character.
-l
lines- Override the 66 line default and reset the page length to
lines. If lines is not greater
than the sum of both the header and trailer depths (in lines), the
pr
utility suppresses output of both the header and trailer, as if the-t
option were in effect. -m
- Merge the contents of multiple files. One line from each file specified by
a file operand is written side by side into text columns of equal fixed
widths, in terms of the number of column positions. The number of text
columns depends on the number of file operands successfully opened. The
maximum number of files merged depends on page width and the per process
open file limit. The options
-e
and-i
are assumed. -n
[char] [width]- Provide width digit line numbering. The default for
width, if not specified, is 5. The number occupies
the first width column positions of each text column
or each line of
-m
output. If char (any nondigit character) is given, it is appended to the line number to separate it from whatever follows. The default for char is a <tab>. Line numbers longer than width columns are truncated. -o
offset- Each line of output is preceded by offset
<spaces>s. If the
-o
option is not specified, the default is zero. The space taken is in addition to the output line width. -r
- Write no diagnostic reports on failure to open a file.
-s
[char]- Separate text columns by the single character char instead of by the appropriate number of <space>s (default for char is the <tab> character).
-t
- Print neither the five-line identifying header nor the five-line trailer usually supplied for each page. Quit printing after the last line of each file without spacing to the end of the page.
-w
width- Set the width of the line to width column positions
for multiple text-column output only. If the
-w
option is not specified and the-s
option is not specified, the default width is 72. If the-w
option is not specified and the-s
option is specified, the default width is 512. - file
- A pathname of a file to be printed. If no file operands are specified, or if a file operand is “-”, the standard input is used. The standard input is used only if no file operands are specified, or if a file operand is “-”.
The -s
option does not allow the option
letter to be separated from its argument, and the options
-e
, -i
, and
-n
require that both arguments, if present, not be
separated from the option letter.
EXIT STATUS
The pr
utility exits 0 on success,
and >0 if an error occurs.
Error messages are written to standard error during the printing process (if output is redirected) or after all successful file printing is complete (when printing to a terminal).
If pr
receives an interrupt while printing
to a terminal, it flushes all accumulated error messages to the screen
before terminating.
NOTES
The interpretation of <form-feed>s in the input stream is that they are special <newline>s which have the side effect of causing a page break. While this works correctly for all cases, strict interpretation also implies that the common convention of placing a <form-feed> on a line by itself is actually interpreted as a blank line, page break, blank line.
RESTRICTIONS
The pr
utility is intended to paginate
input containing basic
ascii(7) text formatting and input streams containing non-printing
<control-characters>,
<escape-sequences>
or long lines may result in formatting errors.
The pr
utility does not
currently understand over-printing using
<back-space>
or
<return>
characters, and except in the case of unmodified single-column output, use
of these characters will cause formatting errors.
SEE ALSO
STANDARDS
The pr
utility is compliant with the
IEEE Std 1003.1-2008 (“POSIX.1”)
specification.
IEEE Std 1003.1-2008
(“POSIX.1”) is relatively silent concerning the
handling of input characters beyond the behavior dictated by the
pr
required command options.
HISTORY
A pr
command appeared in
Version 1 AT&T UNIX.
BUGS
The lack of a line wrapping option, and the specification that truncation does not apply to single-column output frequently results in formatting errors when input lines are longer than actual line width of the output device.
The default width of 72 is archaic and non-obvious since it is
normally ignored in the default single column mode. Using the
-m
option with one column provides a way to truncate
single column output but there's no way to wrap long lines to a fixed line
width.
The default of <tab> for the separator for
the -n
and -s
options often
results in lines apparently wider than expected.