When the lines are a fixed record length, you can call seek() or fseek() in C++, C to get to a known line position.
this is c:
This places the file pointer at the beginning of lineno, assuming recl is fixed.
Otherwise you can try to optimize I/O (see Steven's Advanced Programming in the UBIX Environment) by increasing
buffersize
you have to call setvbuf BEFORE any I/O on the stream
Last edited by jim mcnamara; 05-30-2010 at 12:16 PM..
Hello,
I am new to shell scripting, and I am trying to create a script that reads an input like the following
firstname:lastname:age
firstname:lastname:age
firstname:lastname:age
in a text file. I have a 2 part question. First how do I open the file in a shell script. And then how can... (7 Replies)
hi to all
im having some 20,000 files in that im having some contents say the tabulation of biophysics lab readings ... and i want read tat file and look into tat wether a number say -18.90 is there r not .. and if there print tat no wit file name beside
thank you:D (1 Reply)
So, I want to read line-by-line a text file with unknown number of files....
So:
a=1
b=1
while ; do
b=`sed -n '$ap' test`
a=`expr $a + 1`
$here do something with b etc
done
the problem is that sed does not seem to recognise the $a, even when trying
sed -n ' $a p'
So, I cannot read... (3 Replies)
I need to write a C-Shell script with these properties: It should accept two arguments on the command line. The first argument is the name of a file which contains a list of names, and the second argument is the name of a directory. For each file in the directory, the script should print the... (1 Reply)
I need some help. I would like to read in a text file.
Take a variable such as ROW-D-01, compare it to what's in one line in the text file such as PROD/VM/ROW-D-01 and only input PROD/VM into a variable without the /ROW-D-01.
Is this possible? any help is appreciated. (2 Replies)
I want to add/append the info in the following format to my.txt file.
20130702|abcd20130702.txt FN|SN|DOB
I tried the below script but it throws me some exceptions.
<#!/bin/sh
dt = date '+%y%m%d'members;
echo $dt+|+members+$dt;
/usr/bin/awk -f
BEGIN { FS="|"; OFS="|"; } { print... (6 Replies)
Dear all,
I have a huge txt file (DATA.txt) with the following content . From this txt file, I want the following output using some shell script.
Any help is greatly appreciated.
Greetings,
emily
DATA.txt (snippet of the huge text file)
407202849... (2 Replies)
Hi All
Is there a way to export every line into new txt file where by the title of each txt output are same as the line ?
I have this txt files containing names:
Kandra Vanhooser
Rhona Menefee
Reynaldo Hutt
Houston Rafferty
Charmaine Lord
Albertine Poucher
Juana Maes
Mitch Lobel... (2 Replies)
Really Slick ScreenSavers(1) General Commands Manual Really Slick ScreenSavers(1)NAME
cyclone - tornado screen saver.
SYNOPSIS
cyclone [--root/-r] [--maxfps/-x number] [--vsync/-y number] [--dpms/-M number] [--cyclones/-c number] [--particles/-p number] [--size/-i
number] [--complexity/-C number] [--speed/-e number] [--stretch/-s] [--no-stretch/-S] [--showcurves/-v] [--no-showcurves/-V]
DESCRIPTION
From Terry Walsh (http://reallyslick.com): "This screen saver makes tornadoes on your screen. I wrote it for my storm chasing partner, but
you can have it too."
Ported to Linux by Tugrul Galatali.
OPTIONS --root Draw on the root window.
--maxfps number
Set maximum frame rate.
--vsync number
Limit redraws to specified number of vertical refreshes. 0 - 100. Default: 1
--dpms number
Stop rendering new frames if the display is not on. 0 - 1. Default: 1
--cyclones number
Number of cyclones. 1 - 10. Default: 1
--particles number
Particles per cyclone. 1 - 10000. Default: 200
--size number
Particle size. 1 - 100. Default: 7
--complexity number
Cyclone complexity. 1 - 10. Default: 3
--speed number
Speed. 1 - 100. Default: 10
--stretch
Stretch. Default: True
--showcurves
Show Curves. Default: False
ENVIRONMENT
DISPLAY to get the default host and display number.
SEE ALSO X(1),
COPYRIGHT
Copyright (C) 2002 by Terry Walsh and Tugrul Galatali.
Cyclone is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License version 2 as published
by the Free Software Foundation.
Cyclone is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
AUTHOR
Terry Walsh and Tugrul Galatali <tugrul@galatali.com>
X Version 11 Really Slick ScreenSavers(1)