03-19-2008
cat /dev/null
cat /dev/null > file.txt
9 More Discussions You Might Find Interesting
1. UNIX for Dummies Questions & Answers
Hey guys,
I'd like to delete all text within a text file without actually deleting the file. Is there a vi command I can do from my prompt without actually going into the file and doing a %d i think it is... to remove all the text inside?
I want to add this to a cron job to erase all the data... (2 Replies)
Discussion started by: kingdbag
2 Replies
2. Shell Programming and Scripting
Hi Experts.
I need to list the file and the filename comes from the file ListOfFile.txt.
Basicly I have a filename "ListOfFile.txt" and it contain
Example of ListOfFile.txt
/home/Dave/Program/Tran1.P
/home/Dave/Program/Tran2.P
/home/Dave/Program/Tran3.P
/home/Dave/Program/Tran4.P... (7 Replies)
Discussion started by: tanit
7 Replies
3. UNIX for Dummies Questions & Answers
My website has been hacked and i need to remove a lot of unique files with same content. The files have very similar code:
eval(base64_decodeHow do i find multiple/all the files with the above code and remove them?
Thanks. (10 Replies)
Discussion started by: Boris_yo
10 Replies
4. Shell Programming and Scripting
Hello ,
I have comma delimited file with over 20 fileds that i need to do some validations on. I have to check if certain fields are null and then write the line containing the null field into a new file and then delete the line from the current file.
Can someone tell me how i could go... (2 Replies)
Discussion started by: goddevil
2 Replies
5. Shell Programming and Scripting
Hi,
I am having trouble while using 'sed' with reading files. Please help. I have 3 files. File A, file B and file C. I want to find content of file B in file A and replace it by content in file C.
Thanks a lot!!
Here is a sample of my question.
e.g. (file A: a.txt; file B: b.txt; file... (3 Replies)
Discussion started by: dirkaulo
3 Replies
6. UNIX for Dummies Questions & Answers
Hi
I have a file:
r58778.3|SOURCES={KEY=f665931a...,fw,221-705}|ERRORS={16_1:T,30_1:T,56_1:C,57_1:T,59_1:A,101_1:A,115:-,158_1:C,186_1:A,204:-,271_1:T,305:-,350_1:C,368_1:G,442_1:C,472_1:G,477_1:A}|SOURCE_1="Contig_1092402550638"(f665931a359e36cea0976db191ff60ff09cc816e)
I want to retain... (15 Replies)
Discussion started by: Alyaa
15 Replies
7. Shell Programming and Scripting
Hi,
I have a files in a directory as below :-
ls -1
mqdepth-S1STC02
proc-mq-S1STC01
proc-mq-S1STC02
proc-mq-S1STC03
Whereever i have S1STC i need to copy them into new file with file name S2STC.
expected output :-
ls -1
mqdepth-S2STC02
proc-mq-S2STC01
proc-mq-S2STC02... (3 Replies)
Discussion started by: satishmallidi
3 Replies
8. Shell Programming and Scripting
hi all,
i had the below script
x=`cat input.txt |wc -1`
awk 'NR>1 && NR<'$x' ' input.txt > output.txt
by using above script i am able to remove the head and tail part from the input file and able to append the output to the output.txt but if i run it for second time the output is... (2 Replies)
Discussion started by: hemanthsaikumar
2 Replies
9. Shell Programming and Scripting
Hi friends, here is my problem.
I have three files like this..
cat file1.txt
=======
unix is best
unix is best
linux is best
unix is best
linux is best
linux is best
unix is best
unix is best
cat file2.txt
========
Windows performs better
Mac OS performs better
Windows... (4 Replies)
Discussion started by: Jagadeesh Kumar
4 Replies
RBASH(1) General Commands Manual RBASH(1)
NAME
rbash - restricted bash, see bash(1)
RESTRICTED SHELL
If bash is started with the name rbash, or the -r option is supplied at invocation, the shell becomes restricted. A restricted shell is
used to set up an environment more controlled than the standard shell. It behaves identically to bash with the exception that the follow-
ing are disallowed or not performed:
o changing directories with cd
o setting or unsetting the values of SHELL, PATH, ENV, or BASH_ENV
o specifying command names containing /
o specifying a file name containing a / as an argument to the . builtin command
o specifying a filename containing a slash as an argument to the -p option to the hash builtin command
o importing function definitions from the shell environment at startup
o parsing the value of SHELLOPTS from the shell environment at startup
o redirecting output using the >, >|, <>, >&, &>, and >> redirection operators
o using the exec builtin command to replace the shell with another command
o adding or deleting builtin commands with the -f and -d options to the enable builtin command
o using the enable builtin command to enable disabled shell builtins
o specifying the -p option to the command builtin command
o turning off restricted mode with set +r or set +o restricted.
These restrictions are enforced after any startup files are read.
When a command that is found to be a shell script is executed, rbash turns off any restrictions in the shell spawned to execute the script.
SEE ALSO
bash(1)
GNU Bash-4.0 2004 Apr 20 RBASH(1)