Escape - Revision history

Jimbo: wups, \n isn't applicable to shell sessions

2005-01-28T15:07:53Z

wups, \n isn't applicable to shell sessions

Jimbo: REALLY minor formatting change

2005-01-28T14:56:50Z

REALLY minor formatting change

Jimbo: added examples, minor shell session reformatting, a little rewording, added category

2005-01-28T14:53:53Z

added examples, minor shell session reformatting, a little rewording, added category

20.133.0.12 at 11:27, 28 January 2005

2005-01-28T11:27:58Z

New page

The escape character (\) is used to "escape" special characters.

Special characters are those which have a reserved meaning on UNIX like OSs.

An example is the space character. if you want access a file that has a name with a space in it you need to escape this character, to ensure that it is not treated as a seperator between file names, or between switches.

For example if you typed

emacs my file.txt

emacs would try to open the files "my" and "file.txt".

but if you escaped the space character

emacs my\ file.txt

then emacs would try to open the file "my file.txt".

@@ Line 1: / Line 1: @@
-In unix-like systems, the escape character is not what you get when you press the escape key - it is the backslash (\), which is used to "escape" [[special characters]] when you don't want those special characters to perform their special functions - or, in some cases, to cause normally non-special characters ''to'' perform special functions.
+In unix-like systems, the escape character is not what you get when you press the escape key - it is the backslash (\), which is used to "escape" [[special characters]] when you don't want those special characters to perform their special functions - or, in some cases in [[Perl]], to cause normally non-special characters ''to'' perform special functions.
 The space character is an excellent example of a special character you may want to escape. If you want access a file that has a name with a space in it you need to '''escape''' this character, to ensure that it is not treated as a separator between file names, or between command line switches.
@@ Line 13: / Line 13: @@
 then emacs would open '''my file.txt''' as you intended.
-Conversely, '''n''' is an example of a normally non-special character which becomes special when escaped.  If you want to [[echo]] carriage returns to standard output or to a file, you can't do it by pressing enter - that just executes the echo command (or begins another line in your script, if you're programming).  What you need to do is use '''\n''' - because when you '''escape''' the n character, what you're telling the system is that you want a '''newline'''.
+Conversely, if you're writing a [[Perl]] script, '''n''' is an example of a normally non-special character which becomes special when escaped.  If you want to [[echo]] carriage returns to standard output or to a file, you can't do it by pressing enter - that just executes the echo command (or begins another line in your script, if you're programming).  What you need to do is use '''\n''' - because when you '''escape''' the n character, what you're telling the system is that you want a '''newline'''.
 [[Category:FreeBSD Terminology]]

@@ Line 3: / Line 3: @@
 The space character is an excellent example of a special character you may want to escape. If you want access a file that has a name with a space in it you need to '''escape''' this character, to ensure that it is not treated as a separator between file names, or between command line switches.
-If during a shell session you typed:
+Let's say that you want to edit a file named '''my file.txt'''.  If during a shell session you typed:
   # '''emacs my file.txt'''
-emacs would try to open the files '''my''' and '''file.txt'''.
+emacs would try to open the files '''my''' and '''file.txt''', which is not what you wanted.  But if you escaped the space character:
-−
-but if you escaped the space character:
   # '''emacs my\ file.txt'''
-then emacs would try to open the file '''my file.txt'''.
+then emacs would open '''my file.txt''' as you intended.
 Conversely, '''n''' is an example of a normally non-special character which becomes special when escaped.  If you want to [[echo]] carriage returns to standard output or to a file, you can't do it by pressing enter - that just executes the echo command (or begins another line in your script, if you're programming).  What you need to do is use '''\n''' - because when you '''escape''' the n character, what you're telling the system is that you want a '''newline'''.
 [[Category:FreeBSD Terminology]]

@@ Line 1: / Line 1: @@
-The escape character (\) is used to "escape" special characters.
+In unix-like systems, the escape character is not what you get when you press the escape key - it is the backslash (\), which is used to "escape" [[special characters]] when you don't want those special characters to perform their special functions - or, in some cases, to cause normally non-special characters ''to'' perform special functions.
-Special characters are those which have a reserved meaning on UNIX like OSs.
+The space character is an excellent example of a special character you may want to escape. If you want access a file that has a name with a space in it you need to '''escape''' this character, to ensure that it is not treated as a separator between file names, or between command line switches.
-An example is the space character. if you want access a file that has a name with a space in it you need to escape this character, to ensure that it is not treated as a seperator between file names, or between switches.
+If during a shell session you typed:
-For example if you typed
+ # '''emacs my file.txt'''
-emacs my file.txt
+emacs would try to open the files '''my''' and '''file.txt'''.
-emacs would try to open the files "my" and "file.txt".
+but if you escaped the space character:
-but if you escaped the space character
+ # '''emacs my\ file.txt'''
-emacs my\ file.txt
+then emacs would try to open the file '''my file.txt'''.
-then emacs would try to open the file "my file.txt".
+Conversely, '''n''' is an example of a normally non-special character which becomes special when escaped.  If you want to [[echo]] carriage returns to standard output or to a file, you can't do it by pressing enter - that just executes the echo command (or begins another line in your script, if you're programming).  What you need to do is use '''\n''' - because when you '''escape''' the n character, what you're telling the system is that you want a '''newline'''.