That's only going to work if you can guarantee each line fits into your buffer.
If you can do that, great. If not, you pretty much have to count newline characters. This works, and should be fairly fast as you'd be relying on the OS to page in the data, which should be fast enough. If it's a really big file, and you know you're only going through it once, it'd be faster to use open() and read() with direct IO set so you bypass any page cache (if you're only looking once at each byte of a bunch of gigabytes of data, any caching is wasted cycles):
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)
vavoom(6) Games Manual vavoom(6)
NAME
vavoom - The most advanced Doom/Heretic/Hexen/Strife source port around!
SYNOPSIS
vavoom [ -opengl ] [ -d3d ] [ -particles n ] [ -surfcachesize n ] [ -nosound ] [ -no3dsound ] [ -nomusic ] [ -cddev file ] [ -openal ] [
-nomouse ] [ -nojoy ] [ -nolan ] [ -noudp ] [ -ip ip_addr ] [ -noipx ] [ -mpath ] [ -port n ] { [ -freedoom] | [ -doom ] | [ -doom2 ] | [
-tnt ] | [ -plutonia ] | [ -heretic ] | [ -hexen ] | [ -strife ] } [ -game directory ] [ -devgame directory ] [ -devsnd sndinfo_script ] [
-progs directory ]
DESCRIPTION
Vavoom is a source port based on sources of Doom, Heretic, Hexen and a little bit from Quake. Supported platforms are Windows and Linux.
Vavoom has a graphical launcher (vlaunch).
Graphic Options-opengl
selects OpenGL driver
-d3d selects Direct3D driver
-particles <count>
specifies number of particles to use, default is 2048, but you can't have less than 512 (i.e. you can't disable them)
-surfcachesize <size>
specifies size of surface cache memory, in kilobytes
Sound Options-nosound
disables all sound, music and CD-Audio
-nosfx disables sound
-no3dsound
disables 3D sound, use original mode, Windows version only
-nomusic
disables music
-nocdaudio
disables CD music
-cddev <file>
specifies CD device file, default /dev/cdrom, LINUX version only
-openal
enabled OpenAL driver.
Input Options-nomouse disables mouse
-nojoy disables joystick
Network Options-nolan disables all LAN drivers
-noudp disables TCP/IP driver
-ip <address>
specifies IP address, Windows version only
-noipx disables IPX driver
-mpath enables MPATH TCP/IP driver, DOS version only
-port <port>
sets default LAN port
Game selection-freedoom look only for FreeDoom IWAD files
-doom look only for Doom IWAD files
-doom2 look only for Doom 2: Hell On Earth IWAD files
-tnt look only for Doom TNT: Evilution IWAD files
-plutonia
look only for Doom: The Plutionia Experiment IWAD files
-heretic
look only for Heretic IWAD files
-hexen look only for Hexen IWAD files
-strife
look only for Strife IWAD files
Custom games and development-game <directory> specifies custom game.
-devgame <directory>
like -game, but also sets Vavoom in development mode.
-devsound <SNDINFO_script>
sets sound development mode, uses given SNDINFO script, sounds and music are loaded form archive directory, which is specified in
script.
-progs <directory>
specifies directory where to look for progs. Server progs are loaded from file svprogs.dat, client progs - clprogs.dat. Path must
include ending slash.
Example: -progs progs/myprogs/
-file <file1>[<file2>...]
specifies additional files.
-iwaddir <dir1>[<dir2>...]
specifies additional directories where to look for IWAD files.
Debugging Options-debug creates a debug file basev/debug.txt with all console messages.
-starttime <time>
sets start time, not in LINUX version and dedicated servers
-rhide prints debugfile to stderr, in DOS version Sys_Error exits with call frame traceback
More Information
http://vavoom-engine.com/wiki/index.php?title=Command_line_arguments
/usr/share/doc/vavoom/vavoom.txt.gz
Doom is a registered trademark of id software (http://www.idsoftware.com/).
Author
See the copyright file on /usr/share/doc/vavoom/copyright
games vavoom(6)