'\" et

.TH PR "1P" 2013 "IEEE/The Open Group" "POSIX Programmer's Manual"

.SH PROLOG

This manual page is part of the POSIX Programmer's Manual.

The Linux implementation of this interface may differ (consult

the corresponding Linux manual page for details of Linux behavior),

or the interface may not be implemented on Linux.

.SH NAME

pr

\(em print files

.SH SYNOPSIS

.LP

.nf

pr \fB[\fR+\fIpage\fB] [\fR\(mi\fIcolumn\fB] [\fR\(miadFmrt\fB] [\fR\(mie\fB[\fIchar\fB][\fIgap\fB]] [\fR\(mih \fIheader\fB] [\fR\(mii\fB[\fIchar\fB][\fIgap\fB]]

    [\fR\(mil \fIlines\fB] [\fR\(min\fB[\fIchar\fB][\fIwidth\fB]] [\fR\(mio \fIoffset\fB] [\fR\(mis\fB[\fIchar\fB]] [\fR\(miw \fIwidth\fB] [\fR\(mifp\fB]

    [\fIfile\fR...\fB]\fR

.fi

.SH DESCRIPTION

The

.IR pr

utility is a printing and pagination filter. If multiple input files

are specified, each shall be read, formatted, and written to standard

output. By default, the input shall be separated into 66-line pages,

each with:

.IP " *" 4

A 5-line header that includes the page number, date, time, and

the pathname of the file

.IP " *" 4

A 5-line trailer consisting of blank lines

.P

If standard output is associated with a terminal, diagnostic messages

shall be deferred until the

.IR pr

utility has completed processing.

.P

When options specifying multi-column output are specified, output text

columns shall be of equal width; input lines that do not fit into a

text column shall be truncated. By default, text columns shall be

separated with at least one

<blank>.

.SH OPTIONS

The

.IR pr

utility shall conform to the Base Definitions volume of POSIX.1\(hy2008,

.IR "Section 12.2" ", " "Utility Syntax Guidelines",

except that: the

.IR page

option has a

.BR '\(pl' 

delimiter;

.IR page

and

.IR column

can be multi-digit numbers; some of the option-arguments are optional;

and some of the option-arguments cannot be specified as separate

arguments from the preceding option letter. In particular, the

.BR \(mis

option does not allow the option letter to be separated from its

argument, and the options

.BR \(mie ,

.BR \(mii ,

and

.BR \(min

require that both arguments, if present, not be separated from the

option letter.

.P

The following options shall be supported. In the following option

descriptions,

.IR column ,

.IR lines ,

.IR offset ,

.IR page ,

and

.IR width

are positive decimal integers;

.IR gap

is a non-negative decimal integer.

.IP "\fB+\fIpage\fR" 10

Begin output at page number

.IR page

of the formatted input.

.IP "\fB\(mi\fIcolumn\fR" 10

Produce multi-column output that is arranged in

.IR column

columns (the default shall be 1) and is written down each column in the

order in which the text is received from the input file. This option

should not be used with

.BR \(mim .

The options

.BR \(mie

and

.BR \(mii

shall be assumed for multiple text-column output. Whether or not text

columns are produced with identical vertical lengths is unspecified,

but a text column shall never exceed the length of the page (see the

.BR \(mil

option). When used with

.BR \(mit ,

use the minimum number of lines to write the output.

.IP "\fB\(mia\fP" 10

Modify the effect of the

.BR \(mi \c

.IR column

option so that the columns are filled across the page in a round-robin

order (for example, when

.IR column

is 2, the first input line heads column 1, the second heads column 2,

the third is the second line in column 1, and so on).

.IP "\fB\(mid\fP" 10

Produce output that is double-spaced; append an extra

<newline>

following every

<newline>

found in the input.

.IP "\fB\(mie[\fIchar\fB][\fIgap\fB]\fR" 10

.br

Expand each input

<tab>

to the next greater column position specified by the formula

.IR n *\c

.IR gap +1,

where

.IR n

is an integer > 0. If

.IR gap

is zero or is omitted, it shall default to 8. All

<tab>

characters in the input shall be expanded into the appropriate number of

<space>

characters. If any non-digit character,

.IR char ,

is specified, it shall be used as the input

<tab>.

If the first character of the

.BR \(mie

option-argument is a digit, the entire option-argument shall be assumed

to be

.IR gap .

.IP "\fB\(mif\fP" 10

Use a

<form-feed>

for new pages, instead of the default behavior that uses a sequence of

<newline>

characters. Pause before beginning the first page if the standard output

is associated with a terminal.

.IP "\fB\(miF\fP" 10

Use a

<form-feed>

for new pages, instead of the default behavior that uses a sequence of

<newline>

characters.

.IP "\fB\(mih\ \fIheader\fR" 10

Use the string

.IR header

to replace the contents of the

.IR file

operand in the page header.

.IP "\fB\(mii[\fIchar\fB][\fIgap\fB]\fR" 10

In output, replace

<space>

characters with

<tab>

characters wherever one or more adjacent

<space>

characters reach column positions

.IR gap +1,

2*

.IR gap +1,

3*

.IR gap +1,

and so on. If

.IR gap

is zero or is omitted, default tab settings at every eighth column

position shall be assumed. If any non-digit character,

.IR char ,

is specified, it shall be used as the output

<tab>.

If the first character of the

.BR \(mii

option-argument is a digit, the entire option-argument shall be assumed

to be

.IR gap .

.IP "\fB\(mil\ \fIlines\fR" 10

Override the 66-line default and reset the page length to

.IR lines .

If

.IR lines

is not greater than the sum of both the header and trailer depths (in

lines), the

.IR pr

utility shall suppress both the header and trailer, as if the

.BR \(mit

option were in effect.

.IP "\fB\(mim\fP" 10

Merge files. Standard output shall be formatted so the

.IR pr

utility writes one line from each file specified by a

.IR file

operand, side by side into text columns of equal fixed widths, in terms

of the number of column positions. Implementations shall support

merging of at least nine

.IR file

operands.

.IP "\fB\(min[\fIchar\fB][\fIwidth\fB]\fR" 10

.br

Provide

.IR width -digit

line numbering (default for

.IR width

shall be 5). The number shall occupy the first

.IR width

column positions of each text column of default output or each line of

.BR \(mim

output. If

.IR char

(any non-digit character) is given, it shall be appended to the line

number to separate it from whatever follows (default for

.IR char

is a

<tab>).

.IP "\fB\(mio\ \fIoffset\fR" 10

Each line of output shall be preceded by offset

<space>

characters. If the

.BR \(mio

option is not specified, the default offset shall be zero. The space

taken is in addition to the output line width (see the

.BR \(miw

option below).

.IP "\fB\(mip\fP" 10

Pause before beginning each page if the standard output is directed to

a terminal (\c

.IR pr

shall write an

<alert>

to standard error and wait for a

<carriage-return>

to be read on

.BR /dev/tty ).

.IP "\fB\(mir\fP" 10

Write no diagnostic reports on failure to open files.

.IP "\fB\(mis[\fIchar\fB]\fR" 10

Separate text columns by the single character

.IR char

instead of by the appropriate number of

<space>

characters (default for

.IR char

shall be

<tab>).

.IP "\fB\(mit\fP" 10

Write neither the five-line identifying header nor the five-line

trailer usually supplied for each page. Quit writing after the last

line of each file without spacing to the end of the page.

.IP "\fB\(miw\ \fIwidth\fR" 10

Set the width of the line to

.IR width

column positions for multiple text-column output only. If the

.BR \(miw

option is not specified and the

.BR \(mis

option is not specified, the default width shall be 72. If the

.BR \(miw

option is not specified and the

.BR \(mis

option is specified, the default width shall be 512.

.RS 10 

.P

For single column output, input lines shall not be truncated.

.RE

.SH OPERANDS

The following operand shall be supported:

.IP "\fIfile\fR" 10

A pathname of a file to be written. If no

.IR file

operands are specified, or if a

.IR file

operand is

.BR '\(mi' ,

the standard input shall be used.

.SH STDIN

The standard input shall be used only if no

.IR file

operands are specified, or if a

.IR file

operand is

.BR '\(mi' .

See the INPUT FILES section.

.SH "INPUT FILES"

The input files shall be text files.

.P

The file

.BR /dev/tty

shall be used to read responses required by the

.BR \(mip

option.

.SH "ENVIRONMENT VARIABLES"

The following environment variables shall affect the execution of

.IR pr :

.IP "\fILANG\fP" 10

Provide a default value for the internationalization variables that are

unset or null. (See the Base Definitions volume of POSIX.1\(hy2008,

.IR "Section 8.2" ", " "Internationalization Variables"

the precedence of internationalization variables used to determine the

values of locale categories.)

.IP "\fILC_ALL\fP" 10

If set to a non-empty string value, override the values of all the

other internationalization variables.

.IP "\fILC_CTYPE\fP" 10

Determine the locale for the interpretation of sequences of bytes of

text data as characters (for example, single-byte as opposed to

multi-byte characters in arguments and input files) and which

characters are defined as printable (character class

.BR print ).

Non-printable characters are still written to standard output, but are

not counted for the purpose for column-width and line-length

calculations.

.IP "\fILC_MESSAGES\fP" 10

.br

Determine the locale that should be used to affect the format and

contents of diagnostic messages written to standard error.

.IP "\fILC_TIME\fP" 10

Determine the format of the date and time for use in writing header

lines.

.IP "\fINLSPATH\fP" 10

Determine the location of message catalogs for the processing of

.IR LC_MESSAGES .

.IP "\fITZ\fP" 10

Determine the timezone used to calculate date and time strings written

in header lines. If

.IR TZ

is unset or null, an unspecified default timezone shall be used.

.SH "ASYNCHRONOUS EVENTS"

If

.IR pr

receives an interrupt while writing to a terminal, it shall flush all

accumulated error messages to the screen before terminating.

.SH STDOUT

The

.IR pr

utility output shall be a paginated version of the original file (or

files). This pagination shall be accomplished using either

<form-feed>

characters or a sequence of

<newline>

characters, as controlled by the

.BR \(miF

or

.BR \(mif

option. Page headers shall be generated unless the

.BR \(mit

option is specified. The page headers shall be of the form:

.sp

.RS 4

.nf

\fB

"\en\en%s %s Page %d\en\en\en", <\fIoutput of date\fP>, <\fIfile\fR>, <\fIpage number\fR>

.fi \fR

.P

.RE

.P

In the POSIX locale, the <\fIoutput\ of\ date\fR> field, representing

the date and time of last modification of the input file (or the

current date and time if the input file is standard input), shall be

equivalent to the output of the following command as it would appear if

executed at the given time:

.sp

.RS 4

.nf

\fB

date "+%b %e %H:%M %Y"

.fi \fR

.P

.RE

.P

without the trailing

<newline>,

if the page being written is from standard input. If the page being

written is not from standard input, in the POSIX locale, the same

format shall be used, but the time used shall be the modification time

of the file corresponding to

.IR file

instead of the current time. When the

.IR LC_TIME

locale category is not set to the POSIX locale, a different format and

order of presentation of this field may be used.

.P

If the standard input is used instead of a

.IR file

operand, the <\fIfile\fP> field shall be replaced by a null string.

.P

If the

.BR \(mih

option is specified, the <\fIfile\fP> field shall be replaced by the

.IR header

argument.

.SH STDERR

The standard error shall be used for diagnostic messages and

for alerting the terminal when

.BR \(mip

is specified.

.SH "OUTPUT FILES"

None.

.SH "EXTENDED DESCRIPTION"

None.

.SH "EXIT STATUS"

The following exit values shall be returned:

.IP "\00" 6

Successful completion.

.IP >0 6

An error occurred.

.SH "CONSEQUENCES OF ERRORS"

Default.

.LP

.IR "The following sections are informative."

.SH "APPLICATION USAGE"

A conforming application must protect its first operand, if it starts

with a

<plus-sign>,

by preceding it with the

.BR \(dq\(mi\|\(mi\(dq 

argument that denotes the end of the options. For example,

.IR pr \(pl\c

.IR x

could be interpreted as an invalid page number or a

.IR file

operand.

.SH EXAMPLES

.IP " 1." 4

Print a numbered list of all files in the current directory:

.RS 4 

.sp

.RS 4

.nf

\fB

ls \(mia | pr \(min \(mih "Files in $(pwd)."

.fi \fR

.P

.RE

.RE

.IP " 2." 4

Print

.BR file1

and

.BR file2

as a double-spaced, three-column listing headed by ``file list'':

.RS 4 

.sp

.RS 4

.nf

\fB

pr \(mi3d \(mih "file list" file1 file2

.fi \fR

.P

.RE

.RE

.IP " 3." 4

Write

.BR file1

on

.BR file2 ,

expanding tabs to columns 10, 19, 28, .\|.\|.:

.RS 4 

.sp

.RS 4

.nf

\fB

pr \(mie9 \(mit <file1 >file2

.fi \fR

.P

.RE

.RE

.SH RATIONALE

This utility is one of those that does not follow the Utility Syntax

Guidelines because of its historical origins. The standard developers

could have added new options that obeyed the guidelines (and marked the

old options obsolescent) or devised an entirely new utility; there are

examples of both actions in this volume of POSIX.1\(hy2008. Because of its widespread use by

historical applications, the standard developers decided to exempt this

version of

.IR pr

from many of the guidelines.

.P

Implementations are required to accept option-arguments to the

.BR \(mih ,

.BR \(mil ,

.BR \(mio ,

and

.BR \(miw

options whether presented as part of the same argument or as a separate

argument to

.IR pr ,

as suggested by the Utility Syntax Guidelines. The

.BR \(min

and

.BR \(mis

options, however, are specified as in historical practice because they

are frequently specified without their optional arguments. If a

<blank>

were allowed before the option-argument in these cases, a

.IR file

operand could mistakenly be interpreted as an option-argument in

historical applications.

.P

The text about the minimum number of lines in multi-column output was

included to ensure that a best effort is made in balancing the length

of the columns. There are known historical implementations in which,

for example, 60-line files are listed by

.IR pr

\(mi2 as one column of 56 lines and a second of 4. Although this is not

a problem when a full page with headers and trailers is produced, it

would be relatively useless when used with

.BR \(mit .

.P

Historical implementations of the

.IR pr

utility have differed in the action taken for the

.BR \(mif

option. BSD uses it as described here for the

.BR \(miF

option; System V uses it to change trailing

<newline>

characters on each page to a

<form-feed>

and, if standard output is a TTY device, sends an

<alert>

to standard error and reads a line from

.BR /dev/tty

before the first page. There were strong arguments from both sides of

this issue concerning historical practice and as a result the

.BR \(miF

option was added. XSI-conformant systems support the System V

historical actions for the

.BR \(mif

option.

.P

The <\fIoutput\ of\ date\fP> field in the

.BR \(mil

format is specified only for the POSIX locale. As noted, the format can

be different in other locales. No mechanism for defining this is

present in this volume of POSIX.1\(hy2008, as the appropriate vehicle is a message catalog;

that is, the format should be specified as a ``message''.

.SH "FUTURE DIRECTIONS"

None.

.SH "SEE ALSO"

.IR "\fIexpand\fR\^",

.IR "\fIlp\fR\^"

.P

The Base Definitions volume of POSIX.1\(hy2008,

.IR "Chapter 8" ", " "Environment Variables",

.IR "Section 12.2" ", " "Utility Syntax Guidelines"

.SH COPYRIGHT

Portions of this text are reprinted and reproduced in electronic form

from IEEE Std 1003.1, 2013 Edition, Standard for Information Technology

-- Portable Operating System Interface (POSIX), The Open Group Base

Specifications Issue 7, Copyright (C) 2013 by the Institute of

Electrical and Electronics Engineers, Inc and The Open Group.

(This is POSIX.1-2008 with the 2013 Technical Corrigendum 1 applied.) In the

event of any discrepancy between this version and the original IEEE and

The Open Group Standard, the original IEEE and The Open Group Standard

is the referee document. The original Standard can be obtained online at

http://www.unix.org/online.html .

Any typographical or formatting errors that appear

in this page are most likely

to have been introduced during the conversion of the source files to

man page format. To report such errors, see

https://www.kernel.org/doc/man-pages/reporting_bugs.html .