Unix "look" Command "File too large" Error Message


 
Thread Tools Search this Thread
Top Forums UNIX for Dummies Questions & Answers Unix "look" Command "File too large" Error Message
# 8  
It's 64-bit. When I use input redirect ( < ) on a smaller test file, I get no ouput. I do get the correct output when I omit the redirect symbol.
# 9  
Quote:
Originally Posted by shishong
It's 64-bit. When I use input redirect ( < ) on a smaller test file, I get no ouput.
yes... 'look' doesn't do quite what I thought it did. When you give it no input file it tries to use something in /usr/share/dict!

So no, redirection won't work in this case.

Annoying that your version of look can't support large files on a 64-bit system! This may be a bug.

---------- Post updated at 01:53 PM ---------- Previous update was at 01:46 PM ----------

Looking at the code it doesn't have an explicit built-in limit, it just uses mmap. When I have access to a 64-bit machine later today I'll see what mmap does on 64-bit systems for enormous files.
This User Gave Thanks to Corona688 For This Post:
# 10  
Assuming your file is sorted and has some reasonablly high H value (the leading characters change) try some kind of a radix split to get small files.

For this example assume that most of the letters of the alphabet are found as the leading character of a record and they are all uppercase. This means you can have ~26 smaller files, all of which look will work on.

Code:
awk {file=substr($0,1,1); print $0 > file}' bigfile

This will create 26 smaller files all named A, B, C ... Z. So, now your command becomes:
Code:
string="String value"
look "$string"  ${string:0:1}

${string:0:1} evalautes to the first letter of the search string, which is the file name.
# 11  
I tested the "look" command on a remote server through ssh. The machine has a Darwin Kernel Version 9.8.0 (32-bit). I'm getting the same error message. "File too large". Again, thank you for all the help.
# 12  
Quote:
Originally Posted by shishong
It's 64-bit.
Just did some testing at home. I don't think your Linux system is actually 64-bit; I just mmaped an entire 650-gigabyte file in 64-bit Linux. Granted that was a sparse file, so I went and mapped in all of /dev/sda next.

Even if you have a 64-bit processor, you get none of the benefits unless you install a 64-bit operating system -- namely, each process is limited to 4 gigabytes of virtual memory at most on a 32-bit system.

Naturally 32-bit OSX would have this limit too. Changing the OS without changing the number of bits won't give you more address space.

Try cat /proc/version

Last edited by Corona688; 04-22-2011 at 12:59 AM..
# 13  
Result of cat /proc/version :

Linux version 2.6.35-28-generic (buildd@allspice) (gcc version 4.4.5 (Ubuntu/Linaro 4.4.4-14ubuntu5) ) #50-Ubuntu SMP Fri Mar 18 18:42:20 UTC 2011

I knew I needed a 64-bit system, so I installed the 64-bit version in advance.

When I try "uname -a", I get:
Linux patrick-G53JW 2.6.35-28-generic #50-Ubuntu SMP Fri Mar 18 18:42:20 UTC 2011 x86_64 GNU/Linux

Are there other issues that could have been overlooked thus far?
# 14  
Then perhaps Ubuntu's saddled you with a 32-bit look for some reason. file /usr/bin/look
 

Previous Thread | Next Thread
Thread Tools Search this Thread
Search this Thread:
Advanced Search

Test Your Knowledge in Computers #26
Difficulty: Easy
IPv6 addresses are 256 bits in length.
True or False?

9 More Discussions You Might Find Interesting

1. AIX

Apache 2.4 directory cannot display "Last modified" "Size" "Description"

Hi 2 all, i have had AIX 7.2 :/# /usr/IBMAHS/bin/apachectl -v Server version: Apache/2.4.12 (Unix) Server built: May 25 2015 04:58:27 :/#:/# /usr/IBMAHS/bin/apachectl -M Loaded Modules: core_module (static) so_module (static) http_module (static) mpm_worker_module (static) ... (3 Replies)
Discussion started by: penchev
3 Replies

2. Shell Programming and Scripting

Bash script - Print an ascii file using specific font "Latin Modern Mono 12" "regular" "9"

Hello. System : opensuse leap 42.3 I have a bash script that build a text file. I would like the last command doing : print_cmd -o page-left=43 -o page-right=22 -o page-top=28 -o page-bottom=43 -o font=LatinModernMono12:regular:9 some_file.txt where : print_cmd ::= some printing... (1 Reply)
Discussion started by: jcdole
1 Replies

3. UNIX for Dummies Questions & Answers

Using "mailx" command to read "to" and "cc" email addreses from input file

How to use "mailx" command to do e-mail reading the input file containing email address, where column 1 has name and column 2 containing To e-mail address and column 3 contains cc e-mail address to include with same email. Sample input file, email.txt Below is an sample code where... (2 Replies)
Discussion started by: asjaiswal
2 Replies

4. Solaris

The slices "usr", "opt", "tmp" disappeared!!! Help please.

The system don't boot. on the screen appears following: press enter to maintenance (or type CTRL-D to continue)...I checked with format command. ... the slices "0-root","1-swap","2-backup" exist. ...the slises "3-var","6-usr" -unassigned. :( (16 Replies)
Discussion started by: wolfgang
16 Replies

5. Shell Programming and Scripting

how to use "cut" or "awk" or "sed" to remove a string

logs: "/home/abc/public_html/index.php" "/home/abc/public_html/index.php" "/home/xyz/public_html/index.php" "/home/xyz/public_html/index.php" "/home/xyz/public_html/index.php" how to use "cut" or "awk" or "sed" to get the following result: abc abc xyz xyz xyz (8 Replies)
Discussion started by: timmywong
8 Replies

6. Shell Programming and Scripting

awk command to replace ";" with "|" and ""|" at diferent places in line of file

Hi, I have line in input file as below: 3G_CENTRAL;INDONESIA_(M)_TELKOMSEL;SPECIAL_WORLD_GRP_7_FA_2_TELKOMSEL My expected output for line in the file must be : "1-Radon1-cMOC_deg"|"LDIndex"|"3G_CENTRAL|INDONESIA_(M)_TELKOMSEL"|LAST|"SPECIAL_WORLD_GRP_7_FA_2_TELKOMSEL" Can someone... (7 Replies)
Discussion started by: shis100
7 Replies

7. Shell Programming and Scripting

cat $como_file | awk /^~/'{print $1","$2","$3","$4}' | sed -e 's/~//g'

hi All, cat file_name | awk /^~/'{print $1","$2","$3","$4}' | sed -e 's/~//g' Can this be done by using sed or awk alone (4 Replies)
Discussion started by: harshakusam
4 Replies

8. UNIX for Dummies Questions & Answers

Explain the line "mn_code=`env|grep "..mn"|awk -F"=" '{print $2}'`"

Hi Friends, Can any of you explain me about the below line of code? mn_code=`env|grep "..mn"|awk -F"=" '{print $2}'` Im not able to understand, what exactly it is doing :confused: Any help would be useful for me. Lokesha (4 Replies)
Discussion started by: Lokesha
4 Replies

9. UNIX for Dummies Questions & Answers

Unix "at" / "Cron" Command New Problem...Need help

Hi All, I am trying to schedule a one time job using the at command with the help of shell script for my project. The shell script should take a parameter as a command line argument from the at command itself. Is it possible to take a command line parameter for a shell script in the command... (3 Replies)
Discussion started by: Mohanraj
3 Replies

Featured Tech Videos