Ubuntu Manpage: paste - merge corresponding or subsequent lines of files

NAME

       paste - merge corresponding or subsequent lines of files

SYNOPSIS

       paste [-s][-d list] file...

DESCRIPTION

       The  paste utility shall concatenate the corresponding lines of the given input files, and
       write the resulting lines to standard output.

       The default operation of paste shall concatenate the  corresponding  lines  of  the  input
       files.  The  <newline>  of  every  line  except the line from the last input file shall be
       replaced with a <tab>.

       If an end-of-file condition is detected on one or more input  files,  but  not  all  input
       files,  paste shall behave as though empty lines were read from the files on which end-of-
       file was detected, unless the -s option is specified.

OPTIONS

The paste utility shall conform to the Base Definitions volume of IEEE Std 1003.1-2001,
Section 12.2, Utility Syntax Guidelines.

The following options shall be supported:

-d list
Unless a backslash character appears in list, each character in list is an element
specifying a delimiter character. If a backslash character appears in list, the
backslash character and one or more characters following it are an element
specifying a delimiter character as described below. These elements specify one or
more delimiters to use, instead of the default <tab>, to replace the <newline> of
the input lines. The elements in list shall be used circularly; that is, when the
list is exhausted the first element from the list is reused. When the -s option is
specified:

* The last <newline> in a file shall not be modified.

* The delimiter shall be reset to the first element of list after each file
operand is processed.

When the -s option is not specified:

* The <newline>s in the file specified by the last file operand shall not be
modified.

* The delimiter shall be reset to the first element of list each time a line is
processed from each file.

If a backslash character appears in list, it and the character following it shall be used
to represent the following delimiter characters:

\n
<newline>.

\t
<tab>.

\\
Backslash character.

\0
Empty string (not a null character). If '\0' is immediately followed by the
character 'x' , the character 'X' , or any character defined by the LC_CTYPE digit
keyword (see the Base Definitions volume of IEEE Std 1003.1-2001, Chapter 7,
Locale), the results are unspecified.

If any other characters follow the backslash, the results are unspecified.

-s Concatenate all of the lines of each separate input file in command line order. The
<newline> of every line except the last line in each input file shall be replaced
with the <tab>, unless otherwise specified by the -d option.

OPERANDS

       The following operand shall be supported:

       file   A  pathname of an input file. If '-' is specified for one or more of the files, the
              standard input shall be used; the standard input shall be read one line at a  time,
              circularly,  for each instance of '-' . Implementations shall support pasting of at
              least 12 file operands.

STDIN

       The standard input shall be used only if one or more file operands is '-' . See the  INPUT
       FILES section.

INPUT FILES

       The input files shall be text files, except that line lengths shall be unlimited.

ENVIRONMENT VARIABLES

       The following environment variables shall affect the execution of paste:

       LANG   Provide  a  default  value for the internationalization variables that are unset or
              null. (See the  Base  Definitions  volume  of  IEEE Std 1003.1-2001,  Section  8.2,
              Internationalization Variables for the precedence of internationalization variables
              used to determine the values of locale categories.)

       LC_ALL If set to  a  non-empty  string  value,  override  the  values  of  all  the  other
              internationalization variables.

       LC_CTYPE
              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).

       LC_MESSAGES
              Determine  the  locale  that  should  be  used to affect the format and contents of
              diagnostic messages written to standard error.

       NLSPATH
              Determine the location of message catalogs for the processing of LC_MESSAGES .

ASYNCHRONOUS EVENTS

       Default.

STDOUT

       Concatenated lines of input files shall be separated by the  <tab>  (or  other  characters
       under the control of the -d option) and terminated by a <newline>.

STDERR

       The standard error shall be used only for diagnostic messages.

OUTPUT FILES

       None.

EXTENDED DESCRIPTION

       None.

EXIT STATUS

       The following exit values shall be returned:

        0     Successful completion.

       >0     An error occurred.

CONSEQUENCES OF ERRORS

       If  one  or  more  input  files  cannot  be  opened when the -s option is not specified, a
       diagnostic message shall be written to  standard  error,  but  no  output  is  written  to
       standard  output.  If  the  -s  option  is  specified, the paste utility shall provide the
       default behavior described in Utility Description Defaults .

       The following sections are informative.

APPLICATION USAGE

When the escape sequences of the list option-argument are used in a shell script, they
must be quoted; otherwise, the shell treats the '\' as a special character.

Conforming applications should only use the specific backslash escaped delimiters
presented in this volume of IEEE Std 1003.1-2001. Historical implementations treat '\x' ,
where 'x' is not in this list, as 'x' , but future implementations are free to expand this
list to recognize other common escapes similar to those accepted by printf and other
standard utilities.

Most of the standard utilities work on text files. The cut utility can be used to turn
files with arbitrary line lengths into a set of text files containing the same data. The
paste utility can be used to create (or recreate) files with arbitrary line lengths. For
example, if file contains long lines:

cut -b 1-500 -n file > file1
cut -b 501- -n file > file2

creates file1 (a text file) with lines no longer than 500 bytes (plus the <newline>) and
file2 that contains the remainder of the data from file. Note that file2 is not a text
file if there are lines in file that are longer than 500 + {LINE_MAX} bytes. The original
file can be recreated from file1 and file2 using the command:

paste -d "\0" file1 file2 > file

The commands:

paste -d "\0" ...
paste -d "" ...

are not necessarily equivalent; the latter is not specified by this volume of
IEEE Std 1003.1-2001 and may result in an error. The construct '\0' is used to mean "no
separator" because historical versions of paste did not follow the syntax guidelines, and
the command:

paste -d"" ...

could not be handled properly by getopt().

EXAMPLES

        1. Write out a directory in four columns:

           ls | paste - - - -

        2. Combine pairs of lines from a file into single lines:

           paste -s -d "\t\n" file

RATIONALE

       None.

FUTURE DIRECTIONS

       None.

COPYRIGHT

       Portions of this text are reprinted and  reproduced  in  electronic  form  from  IEEE  Std
       1003.1,  2003  Edition,  Standard  for Information Technology -- Portable Operating System
       Interface (POSIX), The Open Group Base Specifications Issue 6, Copyright (C) 2001-2003  by
       the  Institute  of  Electrical  and  Electronics Engineers, Inc and The Open Group. 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.opengroup.org/unix/online.html .