I have uploaded the $key as a screenshot as I don't have the text version right now..., it's a big string concatenated by "|".
Can you pls. tell me which is better than egrep....
grep.. perl... sed...?
And why should egrep take around 50..60 seconds in an iteration ...?
And will splitting the ${PICKUP_DIR}/new_update file into multiple files and searching each file until a match is found, help in anyway...?
Are the keys separated by a '|' ? Or is the whole thing a key in itself ?
If the keys are separated by '|', then change the file such that each key is on a new line. Then
I dont know if you will have any advantage in splitting up the file.
Hi ,
i'm searching for files over many Aix servers with rsh command using this request :
find /dir1 -name '*.' -exec ls {} \;
and then count them with "wc"
but i would improve this search because it's too long and replace directly find with ls command but "ls *. " doesn't work.
and... (3 Replies)
Hi All,
I am using grep command to find string "abc" in one file .
content of file is
***********
abc = xyz
def= lmn
************
i have given the below mentioned command to redirect the output to tmp file
grep abc file | sort -u | awk '{print #3}' > out_file
Then i am searching... (2 Replies)
hi someone tell me which ways i can improve disk I/O and system process performance.kindly refer some commands so i can do it on my test machine.thanks, Mazhar (2 Replies)
I have a data file of 2 gig
I need to do all these, but its taking hours, any where i can improve performance, thanks a lot
#!/usr/bin/ksh
echo TIMESTAMP="$(date +'_%y-%m-%d.%H-%M-%S')"
function showHelp {
cat << EOF >&2
syntax extreme.sh FILENAME
Specify filename to parse
EOF... (3 Replies)
Hi All,
I have written a script as follows which is taking lot of time in executing/searching only 3500 records taken as input from one file in log file of 12 GB Approximately.
Working of script is read the csv file as an input having 2 arguments which are transaction_id,mobile_number and search... (6 Replies)
Hi ,
i wrote a script to convert dates to the formate i want .it works fine but the conversion is tkaing lot of time . Can some one help me tweek this script
#!/bin/bash
file=$1
ofile=$2
cp $file $ofile
mydates=$(grep -Po '+/+/+' $ofile) # gets 8/1/13
mydates=$(echo "$mydates" | sort |... (5 Replies)
Hello,
Attached is my very simple C++ code to remove any substrings (DNA sequence) of each other, i.e. any redundant sequence is removed to get unique sequences. Similar to sort | uniq command except there is reverse-complementary for DNA sequence. The program runs well with small dataset, but... (11 Replies)
Gents,
Please can u help me to improve this script to be more faster, it works perfectly but for big files take a lot time to end the job..
I see the problem is in the step (while) and in this part the script takes a lot time..
Please if you can find a best way to do will be great.
... (13 Replies)
I have "inherited" a OmniOS (illumos based) server.
I noticed rsync is significantly slower in respect to my reference, FreeBSD 12-CURRENT, running on exactly same hardware.
Using same hardware, same command with same source and target disks, OmniOS r151026 gives:
test@omniosce:~# time... (11 Replies)
Discussion started by: priyadarshan
11 Replies
LEARN ABOUT V7
grep
GREP(1) General Commands Manual GREP(1)NAME
grep, egrep, fgrep - search a file for a pattern
SYNOPSIS
grep [ option ] ... expression [ file ] ...
egrep [ option ] ... [ expression ] [ file ] ...
fgrep [ option ] ... [ strings ] [ file ]
DESCRIPTION
Commands of the grep family search the input files (standard input default) for lines matching a pattern. Normally, each line found is
copied to the standard output; unless the -h flag is used, the file name is shown if there is more than one input file.
Grep patterns are limited regular expressions in the style of ed(1); it uses a compact nondeterministic algorithm. Egrep patterns are full
regular expressions; it uses a fast deterministic algorithm that sometimes needs exponential space. Fgrep patterns are fixed strings; it
is fast and compact.
The following options are recognized.
-v All lines but those matching are printed.
-c Only a count of matching lines is printed.
-l The names of files with matching lines are listed (once) separated by newlines.
-n Each line is preceded by its line number in the file.
-b Each line is preceded by the block number on which it was found. This is sometimes useful in locating disk block numbers by con-
text.
-s No output is produced, only status.
-h Do not print filename headers with output lines.
-y Lower case letters in the pattern will also match upper case letters in the input (grep only).
-e expression
Same as a simple expression argument, but useful when the expression begins with a -.
-f file
The regular expression (egrep) or string list (fgrep) is taken from the file.
-x (Exact) only lines matched in their entirety are printed (fgrep only).
Care should be taken when using the characters $ * [ ^ | ? ' " ( ) and in the expression as they are also meaningful to the Shell. It is
safest to enclose the entire expression argument in single quotes ' '.
Fgrep searches for lines that contain one of the (newline-separated) strings.
Egrep accepts extended regular expressions. In the following description `character' excludes newline:
A followed by a single character matches that character.
The character ^ ($) matches the beginning (end) of a line.
A . matches any character.
A single character not otherwise endowed with special meaning matches that character.
A string enclosed in brackets [] matches any single character from the string. Ranges of ASCII character codes may be abbreviated
as in `a-z0-9'. A ] may occur only as the first character of the string. A literal - must be placed where it can't be mistaken as
a range indicator.
A regular expression followed by * (+, ?) matches a sequence of 0 or more (1 or more, 0 or 1) matches of the regular expression.
Two regular expressions concatenated match a match of the first followed by a match of the second.
Two regular expressions separated by | or newline match either a match for the first or a match for the second.
A regular expression enclosed in parentheses matches a match for the regular expression.
The order of precedence of operators at the same parenthesis level is [] then *+? then concatenation then | and newline.
SEE ALSO ed(1), sed(1), sh(1)DIAGNOSTICS
Exit status is 0 if any matches are found, 1 if none, 2 for syntax errors or inaccessible files.
BUGS
Ideally there should be only one grep, but we don't know a single algorithm that spans a wide enough range of space-time tradeoffs.
Lines are limited to 256 characters; longer lines are truncated.
GREP(1)