it looks like it's *trying* to remove tabs and spaces, with a single space.
the items in square brackets are the list of matches it'll look for, the "*" after the square bracket says "0 or more of these". the "$" is end of line.
Rest is pretty self explanatory (I hope)
Honestly, though, I've never had much luck using sed for replacing control characters, I've had much better luck using the "tr" command.
ie:
(since I can't display a tab properly, I'll do a 2 step, convert to a tab, then from .. obviously you'd just use one or the other in practice )
Say that I want to match any of the following:
abc
def
ghi
The letters will either be "abc", "def", or "ghi", only those three patterns. The numbers will vary, but there will only be numbers between the brackets.
I've only been able to match abc, using the following:
abc.*.
I'm... (1 Reply)
Hi guys,
Pretty new to regex, and i know im doing something wrong here. I'm trying to get a regex command that restricts a string to be 8 characters long, and the first character cannot be 0. Here's what i have so far...
echo "01234" | grep "^{8}*$"
Thanks very much!
-Crawf
... (7 Replies)
Hi,
Is there any quick way to use pull out keys that match a specific regex pattern?
eg
%hash ;
$hash(123,456) = xxx;
$hash(123,457) = xxx;
$hash(123,458) = xxx;
$hash(223,459) = xxx;
I need a fast way to get all the keys that start with 123..
Meaning I should get
... (5 Replies)
I am having trouble parsing rpm filenames in a shell script.. I found a snippet of perl code that will perform the task but I really don't have time to rewrite the entire script in perl. I cannot for the life of me convert this code into something sed-friendly:
if ($rpm =~ /(*)-(*)-(*)\.(.*)/)... (1 Reply)
Hi,
Please help me to understand the bold segments in the below regex.
Both are of same type whose meaning I am looking for.
find . \( -iregex './\{6,10\}./src' \) -type d -maxdepth 2
Output:
./20111210.0/src
In continuation to above:
sed -e 's|./\(*.\{1,3\}\).*|\1|g'
Output: ... (4 Replies)
I have the following line of code that works wonders. I just don't completely understand it as I am just starting to learn regex. Can you help me understand exactly what is happening here?
find . -type f | grep -v '^\.$' | sed 's!\.\/!!' (4 Replies)
# echo "Teest string" | sed 's/e*/=>replaced=</'
=>replaced<=Teest string
So, in the above code , sed replaces at the start. does that mean sed using the pattern e* settles to zero occurence ? Why sed was not able to replace Teest string.
# echo "Teest string" | sed 's/e*//g'
Tst string
... (6 Replies)
Hi everyone,
This regex looks simple and yet it doesn't make sense how it's manipulating the output.
ifconfig -a
eth0 Link encap:Ethernet HWaddr 00:0c:49:c2:35:6v
inet addr:192.16.1.1 Bcast:192.168.226.255 Mask:255.255.255.0
inet6 addr:... (2 Replies)
Hi,
I need some guidance with understanding this Perl script below. I am not the author of the script and the author has not leave any documentation. I supposed it is meant to be 'easy' if you're a Perl or regex guru. I am having problem understanding what regex to use :confused: The script does... (3 Replies)
Hello All,
While googling on regex I came across a site named Regulex Regulex:JavaScript Regular Expression Visualizer
I have written a simple regex ^(a|b|c)(*)@(.*) and could see its visualization; one could export it too, following is the screen shot.
... (3 Replies)
Discussion started by: RavinderSingh13
3 Replies
LEARN ABOUT HPUX
unexpand
expand(1) General Commands Manual expand(1)NAME
expand, unexpand - expand tabs to spaces, and vice versa
SYNOPSIS
tablist] [file ...]
tablist] [file ...]
Obsolescent:
tabstop] tabn] [file ...]
DESCRIPTION
processes the named files or the standard input and writes to the standard output with tabs changed into spaces. Backspace characters are
preserved in the output, and the column count is decreased by one column for tab calculations. For proper tab calculation, if a multi-col-
umn character is to be "backspace'd", it should be followed by multiple backspace characters which equal to it's column width. If a tab
character is found after the last tab position, it is replaced by a single space. is useful for preprocessing character files that contain
tabs (before sorting, looking at specific columns, etc).
recognizes the following command-line options and arguments:
tablist specifies where to set the tab positions instead of the default tablist can take two forms. If it is a single num-
ber, tabs are set tablist spaces apart. tablist can also be a blank- or comma-separated list of increasing positions
where tabs are to be set.
This option is obsolescent and is equivalent to using
This option is obsolescent and is equivalent to using
processes the named files or the standard input and writes to the standard output with spaces changed into tabs where possible. By
default, only leading spaces and tabs are converted to maximal strings of tabs. The default tab position is every 8 characters. Backspace
characters are preserved into the output, and the column count is decreased by one column for tab calculations. For proper tab calcula-
tion, if a multi-column character is to be "backspace'd", it should be followed by multiple backspace characters which equal to it's column
width.
recognizes the following command-line options and arguments:
Tabs are inserted whenever they would compress the resultant file
by replacing two or more spaces before a tab position.
tablist specifies the tab positions. tablist can take two forms. If it is a single number, tabs are set every tablist spa-
ces apart. If tablist is a blank- or comma-separated list of increasing positions, tabs are set at those locations.
The option implies the option. If the option is not specified, the default is equivalent to specifying except that
is not implied for this case.
EXTERNAL INFLUENCES
Environment Variables
determines the interpretation of text as single and/or multi-byte characters.
determines the language in which messages are displayed.
If or is not specified in the environment or is set to the empty string, the value of is used as a default for each unspecified or empty
variable. If is not specified or is set to the empty string, a default of "C" (see lang(5)) is used instead of
If any internationalization variable contains an invalid setting, and behave as if all internationalization variables are set to "C". See
environ(5).
If is set to a non-empty string value, it overrides the values of all the other internationalization variables.
International Code Set Support
Single- and multi-byte character code sets are supported with the exception that do not recognize multi-byte alternative space characters.
STANDARDS CONFORMANCE expand(1)