col(1)
NAME
col --- filter reverse line feeds from input
SYNOPSIS
col [-bfhpx] [-l num]
DESCRIPTION
The col utility filters out reverse (and half reverse) line feeds so that
the output is in the correct order with only forward and half forward
line feeds, and replaces white-space characters with tabs where possible.
This can be useful in processing the output of nroff(1) and tbl(1).
The col utility reads from the standard input and writes to the standard
output.
The options are as follows:
-b Do not output any backspaces, printing only the last character
written to each column position.
-f Forward half line feeds are permitted (``fine'' mode). Normally
characters printed on a half line boundary are printed on the
following line.
-h Do not output multiple spaces instead of tabs (default).
-l num Buffer at least num lines in memory. By default, 128 lines are
buffered.
-p Force unknown control sequences to be passed through unchanged.
Normally, col will filter out any control sequences from the
input other than those recognized and interpreted by itself,
which are listed below.
-x Output multiple spaces instead of tabs.
The control sequences for carriage motion that col understands and their
decimal values are listed in the following table:
ESC-7 reverse line feed (escape then 7)
ESC-8 half reverse line feed (escape then 8)
ESC-9 half forward line feed (escape then 9)
backspace moves back one column (8); ignored in the first column
carriage return (13)
newline forward line feed (10); also does carriage return
shift in shift to normal character set (15)
shift out shift to alternate character set (14)
space moves forward one column (32)
tab moves forward to next tab stop (9)
vertical tab reverse line feed (11)
All unrecognized control characters and escape sequences are discarded.
The col utility keeps track of the character set as characters are read
and makes sure the character set is correct when they are output.
If the input attempts to back up to the last flushed line, col will
display a warning message.
ENVIRONMENT
The LANG, LC_ALL and LC_CTYPE environment variables affect the execution
of col as described in environ(7).
EXIT STATUS
The col utility exits 0 on success, and >0 if an error occurs.
SEE ALSO
colcrt(1), expand(1), nroff(1), tbl(1)
STANDARDS
The col utility conforms to Version 2 of the Single UNIX Specification
("SUSv2").
HISTORY
A col command appeared in Version 6 AT&T UNIX.
Opportunity
Personal Opportunity - Free software gives you access to billions of dollars of software at no cost. Use this software for your business, personal use or to develop a profitable skill. Access to source code provides access to a level of capabilities/information that companies protect though copyrights. Open source is a core component of the Internet and it is available to you. Leverage the billions of dollars in resources and capabilities to build a career, establish a business or change the world. The potential is endless for those who understand the opportunity.
Business Opportunity - Goldman Sachs, IBM and countless large corporations are leveraging open source to reduce costs, develop products and increase their bottom lines. Learn what these companies know about open source and how open source can give you the advantage.
Free Software
Free Software provides computer programs and capabilities at no cost but more importantly, it provides the freedom to run, edit, contribute to, and share the software. The importance of free software is a matter of access, not price. Software at no cost is a benefit but ownership rights to the software and source code is far more significant.
Free Office Software - The Libre Office suite provides top desktop productivity tools for free. This includes, a word processor, spreadsheet, presentation engine, drawing and flowcharting, database and math applications. Libre Office is available for Linux or Windows.
Free Books
The Free Books Library is a collection of thousands of the most popular public domain books in an online readable format. The collection includes great classical literature and more recent works where the U.S. copyright has expired. These books are yours to read and use without restrictions.
Source Code - Want to change a program or know how it works? Open Source provides the source code for its programs so that anyone can use, modify or learn how to write those programs themselves. Visit the GNU source code repositories to download the source.
Education
Study at Harvard, Stanford or MIT - Open edX provides free online courses from Harvard, MIT, Columbia, UC Berkeley and other top Universities. Hundreds of courses for almost all major subjects and course levels. Open edx also offers some paid courses and selected certifications.
Linux Manual Pages - A man or manual page is a form of software documentation found on Linux/Unix operating systems. Topics covered include computer programs (including library and system calls), formal standards and conventions, and even abstract concepts.
