Nice approach indeed!
Could be curtailed to
, including the item list file as well.
I went with this method inserted into a script. It worked well (and very quickly) the first time I tried it, but there was no output the second time. I will have to investigate what I did there.
I also made a second try before there were any responses here. This ended up looking more like the code posted by MadeInGermany where I read in the file to be modified and stored it in an array. I then did a double loop with the outside loop being my list file and the inside loop being the array with the file to be modified. Each item in the list was searched against the lines in the array. If a match was found, the array element was modified to remove the comment and then there was a break in the inner loop. The modified array was printed at the end. This approach means that each file is read in once and the output was written once, instead of once for each list item.
It seems to me that sed must be doing more or less the same thing under the hood. Every list item must be checked against every item in the file to be modified, at least until a match is found. I wasn't able to rationalize if it was more efficient to have one or the other file be the inner loop. The only approach I could think of that would be faster would be to identify the 'Gmax" value on each line of the file to be modified and then loop up that value in a map holding the list. That would, however, involve much more significant parsing of the lines to extract the 'Gmax' value. It is very nice to have a glob match, especially when there isn't a clear and consistent delimiter. If the list was the inner loop, you could delete each array element when a match was found and thus shorten the search as the process continues but deleting and shifting around array elements also takes resources.
Does anyone know what sed is doing to achieve the result so quickly? Is it mainly that is is using compiled code?
I have a dropdown menu built in perl tk (I am using active state perl). I want to select a value from the dropdown menu and I want to be able to perform some other actions depending upon what value is selected. I have all the graphical part made but I dont know how to get the selected value. Any... (0 Replies)
Requirement is:
1. comment and uncomment the line with Shell
Script: /opt/admin/fastpg/bin/fastpg.exe -c -=NET (using fastpg.exe as a search option)
2. display = "Commented" (when its commented) and display = "Uncommented" (when its uncommented)
Its urgent, please let me asap!!!
Thanks in... (2 Replies)
Hi,
I've a list in the following format:
Empdept filedetails buildingNo Area
AAA 444 2 juy
AAA 544 2 kui
AAA 567 4 poi
AAA 734 5 oiu
AAA 444 ... (2 Replies)
I have a combo.cgi here. this is linux environment
What i am going to do is this combobox will list down all the flatfile name in this /u/test/cgi-bin/List directory.
after that, i wanted it to open the flatfile and display the content of the flatfile into another listbox or textarea in this page... (0 Replies)
Hi,
I have the following lines that I would like to see in an array for easy comparisons and printing:
Example 1:
field1,field2,field3,field4,field5
value1,value2,value3,value4,value5Example 2:
field1,field3,field4,field2,field5,field6,field7... (7 Replies)
Hi All,
Need a small help in writing a shell script which can delete a few lines from a file which is currently being used by another process.
File gets appended using tee -a command due to which its size is getting increased.
Contents like :
25/09/2012 05:18 Run ID:56579677-1
My... (3 Replies)
cd path
line1
line2
line3
line4
line5
Lets say thats the sample script...So say if i have to comment the above script, which would be the better way so that whenever i want, i cud comment or uncomment the same.
Thanks (1 Reply)
I have one master file "File1" with all such info in it. I need to grep each object under each list from another file "File2". Can anyone help me with a script for this.
File 1
------
List 1
Object 1
Object 2
List 2
Object 3
Object 1
List 3
Object 2
... (5 Replies)
Hello,
I have some tab delimited text data,
file: final_temp1
aname val
NAME;r'(1,) 3.28584
r'(2,)<tab>
NAME;r'(3,) 6.13003
NAME;r'(4,) 4.18037
r'(5,)<tab>
You can see that the data is incomplete in some cases. There is a trailing tab after the first column for each incomplete row. I... (2 Replies)
Hello,
I need to collect some statistical results from a series of files that are being generated by other software. The files are tab delimited. There are 4 different sets of statistics in each file where there is a line indicating what the statistic set is, followed by 5 lines of values. It... (8 Replies)
Discussion started by: LMHmedchem
8 Replies
LEARN ABOUT DEBIAN
plan9-grep
GREP(1) General Commands Manual GREP(1)NAME
grep, g - search a file for a pattern
SYNOPSIS
grep [ option ... ] pattern [ file ... ]
g [ option ... ] pattern [ file ... ]
DESCRIPTION
Grep searches the input files (standard input default) for lines that match the pattern, a regular expression as defined in regexp(7) with
the addition of a newline character as an alternative (substitute for |) with lowest precedence. Normally, each line matching the pattern
is `selected', and each selected line is copied to the standard output. The options are
-c Print only a count of matching lines.
-h Do not print file name tags (headers) with output lines.
-e The following argument is taken as a pattern. This option makes it easy to specify patterns that might confuse argument parsing,
such as -n.
-i Ignore alphabetic case distinctions. The implementation folds into lower case all letters in the pattern and input before interpre-
tation. Matched lines are printed in their original form.
-l (ell) Print the names of files with selected lines; don't print the lines.
-L Print the names of files with no selected lines; the converse of -l.
-n Mark each printed line with its line number counted in its file.
-s Produce no output, but return status.
-v Reverse: print lines that do not match the pattern.
-f The pattern argument is the name of a file containing regular expressions one per line.
-b Don't buffer the output: write each output line as soon as it is discovered.
Output lines are tagged by file name when there is more than one input file. (To force this tagging, include /dev/null as a file name
argument.)
Care should be taken when using the shell metacharacters $*[^|()= and newline in pattern; it is safest to enclose the entire expression in
single quotes '...'. An expression starting with '*' will treat the rest of the expression as literal characters.
G invokes grep with -n and forces tagging of output lines by file name. If no files are listed, it searches all files matching
*.C *.b *.c *.h *.m *.cc *.java *.cgi *.pl *.py *.tex *.ms
SOURCE
/src/cmd/grep
/bin/g
SEE ALSO ed(1), awk(1), sed(1), sam(1), regexp(7)DIAGNOSTICS
Exit status is null if any lines are selected, or non-null when no lines are selected or an error occurs.
GREP(1)