Login or Register to Ask a Question and Join Our Community


Shell Programming and Scripting

Removing the entire file contents using unix shell script.

Login to Discuss or Reply to this Discussion in Our Community

 
Thread Tools Search this Thread
Top Forums Shell Programming and Scripting Removing the entire file contents using unix shell script.
# 1  
Old 02-10-2009
Java Removing the entire file contents using unix shell script.
I need to remove the entire file contents in file using the shell script.

Actually the grap -v command will create one more file and it occupy the space also.

I need to remove the entire file contents without creating new file using the shell scripting.

Please help me.
Last edited by praka; 02-10-2009 at 02:58 AM.. Reason: changed the title.
# 2  
Old 02-10-2009
if u want to nullify the file use
:>filename
# 3  
Old 02-10-2009
Bug
Thanks for your information.
Can you please give complete script.
# 4  
Old 02-10-2009
Either
Code:
$ :>file

or, a bit more brutal,
Code:
$ rm -f file && touch file

The second one, though, will cause quite some havoc if a process still has a filehandle open on it.
# 5  
Old 02-10-2009
whether this code $ :>file
will remove all contents from file and put into another file?

If yes then i need code to remove all the file contents without creating new file.

The other code is ok. remove the file and touch file.
# 6  
Old 02-10-2009
':>file' tells the shell to redirect the output of the NOOP command (which is none) to "file", creating it if it doesn't exist, or truncating it if it exists.
Login or Register to Ask a Question

Previous Thread | Next Thread

10 More Discussions You Might Find Interesting

1. Shell Programming and Scripting

Shell script (sh file) logic to compare contents of one file with another file and output to file

Shell script logic Hi I have 2 input files like with file 1 content as (file1) "BRGTEST-242" a.txt "BRGTEST-240" a.txt "BRGTEST-219" e.txt File 2 contents as fle(2) "BRGTEST-244" a.txt "BRGTEST-244" b.txt "BRGTEST-231" c.txt "BRGTEST-231" d.txt "BRGTEST-221" e.txt I want to get... (22 Replies)
Discussion started by: pottic
22 Replies

2. Shell Programming and Scripting

Modifying contents of the file in shell script

Hello all, I have a Kconfig file that looks like something below ... ================================ menu "Application type" config GUI_TYPE_STANDARD bool "Standard Application" source "cfg/config/std.in" source... (12 Replies)
Discussion started by: anand.shah
12 Replies

3. Shell Programming and Scripting

Subsituting contents of entire file to middle of another file using awk

Hi I have a data file 'File2' consisting of 105670 lines. I want to copy and paste 17928 lines from 'File1' to 'File2' but I want to place it in between lines 21 and 17950 of 'File2'. How do I do it in awk? For example- File A has 5 lines X Y 1 2 3 4 5 6 7 8 9 and File B has A b... (1 Reply)
Discussion started by: ananyob
1 Replies

4. Shell Programming and Scripting

Subsituting contents of entire file to middle of another file using awk

Hi I have a data file 'File2' consisting of 105670 lines. I want to copy and paste 17928 lines from 'File1' to 'File2' but I want to place it in between lines 21 and 17950 of 'File2'. How do I do it in awk? For example- File A has 5 lines X Y 1 2 3 4 5 6 7 8 9 and File B has A b... (1 Reply)
Discussion started by: ananyob
1 Replies

5. UNIX for Dummies Questions & Answers

Copy entire contents of file to clipboard

Hi, I am trying to figure out how to copy the contents of a file to the clipboard, then paste into a command. i.e copy contents of file /path/filename.txt to <command> <paste text> Hope that makes sense. Basically tryting to copy the text for use in a command without having to open the... (8 Replies)
Discussion started by: JCA70
8 Replies

6. Shell Programming and Scripting

shell script to compare file contents

Hello Has anyone got an example shell script that I can use to compare the contents of two files. The files should contain the same contents, eg. file1.txt apple pear grape file2.txt apple pear grape (2 Replies)
Discussion started by: deedaz
2 Replies

7. Shell Programming and Scripting

Shell script for converting file contents into CSV

Hi, I am new in unix, I just want to replace some values from text file according to column numbers. Like, I am having a table as given below: val1 val2 val3 val4 val5 val6 val7 val8 val9 val10 val11 val12 val13 Now i want... (5 Replies)
Discussion started by: rish_max
5 Replies

8. Shell Programming and Scripting

Remove spaces from first field, and write entire contents into other text file

Hi all, I have searched and found various threads about removing spaces from a field within a text file. Unfortunately, I have not found exactly what I'm looking for, nor am I adept enough to modify what I've found into what I need. I use the following command to remove the first line... (3 Replies)
Discussion started by: carriehoff
3 Replies

9. Shell Programming and Scripting

update file contents using shell script

Hi, I am having a file which contains as below Names(aaaa ,bbbb ,cccc ,dddd) now i want the file to be updated with new value 'eeee' as below Names(aaaa ,bbbb ,cccc ,dddd ,eeee) Is there a way to script this ? Thanks, (5 Replies)
Discussion started by: drams
5 Replies

10. Shell Programming and Scripting

Unix shell script to parse the contents of comma-separated file

Dear All, I have a comma-separated file. 1. The first line of the file(header) should have 4 commas(5 fields). 2. The last line of the file should have 1 comma(2 fields). Pls help me in checking this condition in a shell script. And the number of lines between the first line and last... (11 Replies)
Discussion started by: KrishnaSaran
11 Replies
Login or Register to Ask a Question