Sponsored Content
Top Forums UNIX for Beginners Questions & Answers Performance issue to read line by line Post 302972409 by RudiC on Thursday 5th of May 2016 03:00:00 AM
Old 05-05-2016
In principle, the idea of switching to awk for the entire processing is not a bad one, although you shouldn't expect another performance improvement as noticeable as the one gained before.
But - you can't use shell syntax inside awk. E.g.
Code:
${record%"${record#????}"  ---> substr (record, 1, 4)
a2=$(( a2 + 1 ))           ---> a2+=1
$xyz                       ---> xyz (unless you want to access field xyz)


And, don't cata file into awk's stdin - awk can open and read a file immediately.
 

10 More Discussions You Might Find Interesting

1. Shell Programming and Scripting

bash: read file line by line (lines have '\0') - not full line has read???

I am using the while-loop to read a file. The file has lines with null-terminated strings (words, actually.) What I have by that reading - just a first word up to '\0'! I need to have whole string up to 'new line' - (LF, 10#10, 16#A) What I am doing wrong? #make file 'grb' with... (6 Replies)
Discussion started by: alex_5161
6 Replies

2. Shell Programming and Scripting

While loop read line Issue

Hi I am using while loop, below, to read lines from a very large file, around 400,000 rows. The script works fine until around line 300k but then starts giving incorrect result. I have tried running the script with a smaller data set and it works fine. I made sure to include the line where... (2 Replies)
Discussion started by: saurabhkumar198
2 Replies

3. Shell Programming and Scripting

Multi Line 'While Read' command issue when using sh -c

Hi, I'm trying to run the following command using sh -c ie sh -c "while read EachLine do rm -f $EachLine ; done < file_list.lst;" It doesn't seem to do anything. When I run this at the command line, it does remove the files contained in the list so i know the command works ie... (4 Replies)
Discussion started by: chrispward
4 Replies

4. Shell Programming and Scripting

while read LINE issue

Hi, This is the script and the error I am receiving Can anyone please suggest ? For the exmaple below assume we are using vg01 #!/bin/ksh echo "##### Max Mount Count Fixer #####" echo "Please insert Volume Group name to check" read VG lvs |grep $VG | awk {'print $1'} > /tmp/audit.log ... (2 Replies)
Discussion started by: galuzan
2 Replies

5. Shell Programming and Scripting

how to read the contents of two files line by line and compare the line by line?

Hi All, I'm trying to figure out which are the trusted-ips and which are not using a script file.. I have a file named 'ip-list.txt' which contains some ip addresses and another file named 'trusted-ip-list.txt' which also contains some ip addresses. I want to read a line from... (4 Replies)
Discussion started by: mjavalkar
4 Replies

6. Shell Programming and Scripting

Need a program that read a file line by line and prints out lines 1, 2 & 3 after an empty line...

Hello, I need a program that read a file line by line and prints out lines 1, 2 & 3 after an empty line... An example of entries in the file would be: SRVXPAPI001 ERRO JUN24 07:28:34 1775 REASON= 0000, PROCID= #E506 #1065: TPCIPPR, INDEX= 003F ... (8 Replies)
Discussion started by: Ferocci
8 Replies

7. Shell Programming and Scripting

How to read file line by line and compare subset of 1st line with 2nd?

Hi all, I have a log file say Test.log that gets updated continuously and it has data in pipe separated format. A sample log file would look like: <date1>|<data1>|<url1>|<result1> <date2>|<data2>|<url2>|<result2> <date3>|<data3>|<url3>|<result3> <date4>|<data4>|<url4>|<result4> What I... (3 Replies)
Discussion started by: pat_pramod
3 Replies

8. Shell Programming and Scripting

Read line, issue with leading - and {}'s

Heyas With my forum search term 'issue with leading dash' i found 2 closed threads which sadly didnt help me. Also me was to eager to add the script, that i didnt properly test, and just now figured this issue. So i have this code: if ] then while read line do line="${line/-/'\-'}"... (7 Replies)
Discussion started by: sea
7 Replies

9. Shell Programming and Scripting

[BASH] read 'line' issue with leading tabs and virtual line breaks

Heyas I'm trying to read/display a file its content and put borders around it (tui-cat / tui-cat -t(ypwriter). The typewriter-part is a 'bonus' but still has its own flaws, but thats for later. So in some way, i'm trying to rewrite cat using bash and other commands. But sadly it fails on... (2 Replies)
Discussion started by: sea
2 Replies

10. Shell Programming and Scripting

Performance issue - to read line by line

All- We have a performance issue in reading a file line by line. Please find attached scripts for the same. Currently it is taking some 45 min to parse "512444" lines. Could you please have a look at it and provide any suggestions to improve the performance. Thanks, Balu ... (12 Replies)
Discussion started by: balu1729
12 Replies
XMLIF(1)							       xmlif								  XMLIF(1)

NAME
xmlif - conditional processing instructions for XML SYNOPSIS
xmlif [attrib=value...] DESCRIPTION
xmlif filters XML according to conditionalizing markup. This can be useful for formatting one of several versions of an XML document depending on conditions passed to the command. Attribute/value pairs from the command line are matched against the attributes associated with certain processing instructions in the document. The instructions are <?xmlif if?> and its inverse <?xmlif if not?>, <?xmlif elif?> and its inverse <?xmlif elif not?>, <?xmlif else?>, and <?xmlif fi?>. Argument/value pairs given on the command line are checked against the value of corresponding attributes in the conditional processing instructions. An `attribute match' happens if an attribute occurs in both the command-line arguments and the tag, and the values match. An `attribute mismatch' happens if an attribute occurs in both the command-line arguments and the tag, but the values do not match. Spans between <?xmlif if?> or <?xmlif elif?> and the next conditional processing instruction at the same nesting level are passed through unaltered if there is at least one attribute match and no attribute mismatch; spans between <?xmlif if not?> and <?xmlif elif not?> and the next conditional processing instruction are passed otherwise. Spans between <?xmlif else?> and the next conditional-processing tag are passed through only if no previous span at the same level has been passed through. <?xmlif if?> and <?xmlif fi?> (and their `not' variants) change the current nesting level; <?xmlif else?> and <?xmlif elif?> do not. All these processing instructions will be removed from the output produced. Aside from the conditionalization, all other input is passed through untouched; in particular, entity references are not resolved. Value matching is by string equality, except that "|" in an attribute value is interpreted as an alternation character. Thus, saying foo='red|blue' on the command line enables conditions red and blue. Saying color='black|white' in a tag matches command-line conditions color='black' and color='white'. Here is an example: Always issue this text. <?xmlif if condition='html'?> Issue this text if 'condition=html' is given on the command line. <?xmlif elif condition='pdf|ps'?> Issue this text if 'condition=pdf' or 'condition=ps' is given on the command line. <?xmlif else?> Otherwise issue this text. <?xmlif fi?> Always issue this text. AUTHOR
Eric S. Raymond <esr@snark.thyrsus.com> Author of xmlif program Linux April 2009 XMLIF(1)
All times are GMT -4. The time now is 03:34 AM.
Unix & Linux Forums Content Copyright 1993-2022. All Rights Reserved.
Privacy Policy