Could you not find a followed by b followed by c with just: -v negates results:
-l (ell) will return the filename(s) with matches, instead of the matches themselves.
If you want only to extract the exactabc match (assuming that's variable, and thus useful), use the -o option, if available, otherwise switch to sed, or another tool.
Use the -q option if you only care about the result, and not the output.
I'm using the URL Regex feature of Squid for allowing sites via a list of regex strings to match allowed domains. The regex was actually copied from our previous proxy solution and it seemed to "just work". But, we've recently discovered that some domains (likely due to virtual hosts or host... (2 Replies)
Let's say I'm trying to match potentially multiple sets of parentheses. Is there a way in a regular expression to force a match of closing parentheses specifically in the number of the opening parentheses?
For example, if the string is "((foo bar))", I want to be able to say "match any number of... (7 Replies)
Hi folks,
Lets say I have the following text file:
name, lastname, 1234, name.lastname@test.com
name1, lastname1, name2.lastname2@test.com, 2345
name, 3456, lastname, name3.lastname3@test.com
4567, name, lastname, name4.lastname4@test.com
I now need the following output:
1234... (5 Replies)
Hello,
I'm working on unix with grep (GNU grep) 2.5.1. I'm going through some of the newer regex syntax using Regular Expression Reference - Advanced Syntax a guide.
ls -aLl /bin | grep "\(x\)"
Which works, just highlights 'x' where ever, when ever.
I'm trying to to get (?:) to work but... (4 Replies)
I need scan through some files, then open the file one by one and scan inside the file using perl to see if it contain a start tag and end tag which the end tag is the mirror image of the start tag, the start tag and end tag only have 5 char. And inside the file there is "http://". It is just a... (5 Replies)
Hi,
I've a logfile which i need to parse and get the logs depending upon the user input. here, i'm providing an option to enter the string which can be matched with the log entries.
e.g. one of the logfile entry reads like this -
$str = " mpgw(BLUESOAPFramework):... (6 Replies)
Hi,
I'm trying to validate if a string matches a regular expression, but it is not working. Am I missing something? Do I need to scape any of the characters?
if echo 'en-GB' | egrep '({1,8})(-{1,8})*' >/dev/null; then
echo Valid value
fi
Thanks in advance (6 Replies)
Fairly straightforward, but I'm having an awful time getting what I thought was a simple regex to work. I'll give the command I was playing with, and I'm aware why this one doesn't work (the 1,3 is off the A-Z, not the whole expression), I just don't know what the fix is:
Actual Output(s):
$... (5 Replies)
grep -v will exclude matching lines, but I want something that will print all lines but exclude a matching field. The pattern that I want excluded is '/mnt/svn'
If there is a better solution than awk I am happy to hear about it, but I would like to see this done in awk as well. I know I can... (11 Replies)
Hi all,
I want to extract rows with the pattern ALPHANUMERIC/ALPHANUMNERIC in the 2nd column.
I dont wan rows with more than 1 slash or without any slash in 2nd column.
a a/b
b a/b/c
c a/b//c
d t/y
e r
f /f
I came up with the regex
grep '\/$' file
a a/b
b a/b/c
d t/y (3 Replies)
Discussion started by: jianp83
3 Replies
LEARN ABOUT DEBIAN
unbuffer
UNBUFFER(1) General Commands Manual UNBUFFER(1)NAME
unbuffer - unbuffer output
SYNOPSIS
unbuffer program [ args ]
INTRODUCTION
unbuffer disables the output buffering that occurs when program output is redirected from non-interactive programs. For example, suppose
you are watching the output from a fifo by running it through od and then more.
od -c /tmp/fifo | more
You will not see anything until a full page of output has been produced.
You can disable this automatic buffering as follows:
unbuffer od -c /tmp/fifo | more
Normally, unbuffer does not read from stdin. This simplifies use of unbuffer in some situations. To use unbuffer in a pipeline, use the
-p flag. Example:
process1 | unbuffer -p process2 | process3
CAVEATS
unbuffer -p may appear to work incorrectly if a process feeding input to unbuffer exits. Consider:
process1 | unbuffer -p process2 | process3
If process1 exits, process2 may not yet have finished. It is impossible for unbuffer to know long to wait for process2 and process2 may
not ever finish, for example, if it is a filter. For expediency, unbuffer simply exits when it encounters an EOF from either its input or
process2.
In order to have a version of unbuffer that worked in all situations, an oracle would be necessary. If you want an application-specific
solution, workarounds or hand-coded Expect may be more suitable. For example, the following example shows how to allow grep to finish pro-
cessing when the cat before it finishes first. Using cat to feed grep would never require unbuffer in real life. It is merely a place-
holder for some imaginary process that may or may not finish. Similarly, the final cat at the end of the pipeline is also a placeholder
for another process.
$ cat /tmp/abcdef.log | grep abc | cat
abcdef
xxxabc defxxx
$ cat /tmp/abcdef.log | unbuffer grep abc | cat
$ (cat /tmp/abcdef.log ; sleep 1) | unbuffer grep abc | cat
abcdef
xxxabc defxxx
$
BUGS
The man page is longer than the program.
SEE ALSO
"Exploring Expect: A Tcl-Based Toolkit for Automating Interactive Programs" by Don Libes, O'Reilly and Associates, January 1995.
AUTHOR
Don Libes, National Institute of Standards and Technology
1 June 1994 UNBUFFER(1)