convention used on GNU, Unix, and other POSIX-compliant systems.
@cindex end-of-line conversion on MS-DOS/MS-Windows
- By contrast, MS-DOS and MS-Windows normally use carriage-return linefeed,
-a two-character sequence, to separate text lines. (Linefeed is the same
-character as newline.) Therefore, convenient editing of typical files
-with Emacs requires conversion of these end-of-line (EOL) sequences.
-And that is what Emacs normally does: it converts carriage-return
-linefeed into newline when reading files, and converts newline into
-carriage-return linefeed when writing files. The same mechanism that
-handles conversion of international character codes does this conversion
-also (@pxref{Coding Systems}).
+ By contrast, MS-DOS and MS-Windows normally use carriage return
+followed by linefeed, a two-character sequence, to separate text
+lines. (Linefeed is the same character as newline.) Therefore,
+convenient editing of typical files with Emacs requires conversion of
+these end-of-line (EOL) sequences. And that is what Emacs normally
+does: it converts carriage return followed by linefeed into newline
+when reading files, and converts newline into carriage return followed
+by linefeed when writing files. The same mechanism that handles
+conversion of international character codes does this conversion also
+(@pxref{Coding Systems}).
@cindex cursor location, on MS-DOS
@cindex point location, on MS-DOS
not agree with the file size information known to the operating system.
In addition, if Emacs recognizes from a file's contents that it uses
-newline rather than carriage-return linefeed as its line separator, it
-does not perform EOL conversion when reading or writing that file.
-Thus, you can read and edit files from GNU and Unix systems on MS-DOS
-with no special effort, and they will retain their Unix-style
-end-of-line convention after you edit them.
+newline rather than carriage return followed by linefeed as its line
+separator, it does not perform EOL conversion when reading or writing
+that file. Thus, you can read and edit files from GNU and Unix
+systems on MS-DOS with no special effort, and they will retain their
+Unix-style end-of-line convention after you edit them.
The mode line indicates whether end-of-line translation was used for
the current buffer. If MS-DOS end-of-line translation is in use for the
the coding system mnemonic near the beginning of the mode line
(@pxref{Mode Line}). If no EOL translation was performed, the string
@samp{(Unix)} is displayed instead of the backslash, to alert you that the
-file's EOL format is not the usual carriage-return linefeed.
+file's EOL format is not the usual carriage return followed by linefeed.
@cindex DOS-to-Unix conversion of files
To visit a file and specify whether it uses DOS-style or Unix-style
end-of-line, specify a coding system (@pxref{Text Coding}). For
example, @kbd{C-x @key{RET} c unix @key{RET} C-x C-f foobar.txt}
visits the file @file{foobar.txt} without converting the EOLs; if some
-line ends with a carriage-return linefeed pair, Emacs will display
-@samp{^M} at the end of that line. Similarly, you can direct Emacs to
-save a buffer in a specified EOL format with the @kbd{C-x @key{RET} f}
-command. For example, to save a buffer with Unix EOL format, type
-@kbd{C-x @key{RET} f unix @key{RET} C-x C-s}. If you visit a file
-with DOS EOL conversion, then save it with Unix EOL format, that
-effectively converts the file to Unix EOL style, like the
+line ends with a carriage return followed by linefeed pair, Emacs will
+display @samp{^M} at the end of that line. Similarly, you can direct
+Emacs to save a buffer in a specified EOL format with the @kbd{C-x
+@key{RET} f} command. For example, to save a buffer with Unix EOL
+format, type @kbd{C-x @key{RET} f unix @key{RET} C-x C-s}. If you
+visit a file with DOS EOL conversion, then save it with Unix EOL
+format, that effectively converts the file to Unix EOL style, like the
@code{dos2unix} program.
@cindex untranslated file system
In addition to converting various representations of non-@acronym{ASCII}
characters, a coding system can perform end-of-line conversion. Emacs
handles three different conventions for how to separate lines in a file:
-newline (Unix), carriage-return linefeed (DOS), and just
-carriage-return (Mac).
+newline (Unix), carriage return followed by linefeed (DOS), and just
+carriage return (Mac).
@table @kbd
@item C-h C @var{coding} @key{RET}
@code{no-conversion}, which means no conversion of any kind---specifies
how and whether to convert printing characters, but leaves the choice of
end-of-line conversion to be decided based on the contents of each file.
-For example, if the file appears to use the sequence carriage-return
-linefeed to separate lines, DOS end-of-line conversion will be used.
+For example, if the file appears to use the sequence carriage return
+and linefeed to separate lines, DOS end-of-line conversion will be used.
Each of the listed coding systems has three variants, which specify
exactly what to do for end-of-line conversion:
on Unix and GNU systems, and macOS.)
@item @dots{}-dos
-Assume the file uses carriage-return linefeed to separate lines, and do
-the appropriate conversion. (This is the convention normally used on
-Microsoft systems.@footnote{It is also specified for MIME @samp{text/*}
-bodies and in other network transport contexts. It is different
-from the SGML reference syntax record-start/record-end format, which
-Emacs doesn't support directly.})
+Assume the file uses carriage return followed by linefeed to separate
+lines, and do the appropriate conversion. (This is the convention
+normally used on Microsoft systems.@footnote{It is also specified for
+MIME @samp{text/*} bodies and in other network transport contexts. It
+is different from the SGML reference syntax record-start/record-end
+format, which Emacs doesn't support directly.})
@item @dots{}-mac
-Assume the file uses carriage-return to separate lines, and do the
+Assume the file uses carriage return to separate lines, and do the
appropriate conversion. (This was the convention used in Classic Mac
OS.)
@end table
@vindex inhibit-eol-conversion
@cindex DOS-style end-of-line display
Emacs recognizes which kind of end-of-line conversion to use based on
-the contents of the file: if it sees only carriage-returns, or only
-carriage-return linefeed sequences, then it chooses the end-of-line
-conversion accordingly. You can inhibit the automatic use of
-end-of-line conversion by setting the variable @code{inhibit-eol-conversion}
-to non-@code{nil}. If you do that, DOS-style files will be displayed
-with the @samp{^M} characters visible in the buffer; some people
-prefer this to the more subtle @samp{(DOS)} end-of-line type
-indication near the left edge of the mode line (@pxref{Mode Line,
-eol-mnemonic}).
+the contents of the file: if it sees only carriage returns, or only
+carriage return followed by linefeed sequences, then it chooses the
+end-of-line conversion accordingly. You can inhibit the automatic use
+of end-of-line conversion by setting the variable
+@code{inhibit-eol-conversion} to non-@code{nil}. If you do that,
+DOS-style files will be displayed with the @samp{^M} characters
+visible in the buffer; some people prefer this to the more subtle
+@samp{(DOS)} end-of-line type indication near the left edge of the
+mode line (@pxref{Mode Line, eol-mnemonic}).
@vindex inhibit-iso-escape-detection
@cindex escape sequences in files
(@pxref{Coding Systems, end-of-line conversion}) for encoding the
current buffer. For example, @kbd{C-x @key{RET} f dos @key{RET}} will
cause Emacs to save the current buffer's text with DOS-style
-carriage-return linefeed line endings.
+carriage return followed by linefeed line endings.
@kindex C-x RET c
@findex universal-coding-system-argument
string is displayed, that indicates a nontrivial end-of-line
convention for encoding a file. Usually, lines of text are separated
by @dfn{newline characters} in a file, but two other conventions are
-sometimes used. The MS-DOS convention uses a carriage-return
+sometimes used. The MS-DOS convention uses a carriage return
character followed by a linefeed character; when editing such
files, the colon changes to either a backslash (@samp{\}) or
@samp{(DOS)}, depending on the operating system. Another convention,
-employed by older Macintosh systems, uses a carriage-return
+employed by older Macintosh systems, uses a carriage return
character instead of a newline; when editing such files, the colon
changes to either a forward slash (@samp{/}) or @samp{(Mac)}. On some
systems, Emacs displays @samp{(Unix)} instead of the colon for files
used on various systems for representing end of line in files. The
Unix convention, used on GNU and Unix systems, is to use the linefeed
character (also called newline). The DOS convention, used on
-MS-Windows and MS-DOS systems, is to use a carriage-return and a
+MS-Windows and MS-DOS systems, is to use a carriage return and a
linefeed at the end of a line. The Mac convention is to use just
-carriage-return. (This was the convention used in Classic Mac OS.)
+carriage return. (This was the convention used in Classic Mac OS.)
@cindex base coding system
@cindex variant coding system
For example, @samp{(calc-eval "vx5\rVR+" 'macro)} pushes the
vector @samp{[1,2,3,4,5]} on the stack and then replaces it
with the sum of those numbers. Note that @samp{\r} is the Lisp
-notation for the carriage-return, @key{RET}, character.
+notation for the carriage return, @key{RET}, character.
If your keyboard macro wishes to pop the stack, @samp{\C-d} is
safer than @samp{\177} (the @key{DEL} character) because some
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