Can anyone give me a clue why this code doesn't work as expected? The function count_collatz_step() take one parameter which a number that need to calculate collatz until it reaches 1. The func should return steps it takes.
how can i use a rlogin with out entered a password,
someone tell me about configure the next files
/.rhosts
/etc/hosts.equiv and /etc/hosts
but i not sure about that, or there are not enough
could you tell me how to do that? (3 Replies)
anyone can help me how to implement the timer on AIX?
I tried with 'setitimer' and its related functions, but it does not work correctly,the program exited each time.
thanks (2 Replies)
Hi,
Can you please help me in implementing a timer based polling for function in C? ie. the function should be called in say 30secs(when 30secs has lapsed).
Thanks (7 Replies)
Hi all,
could any of you please help me on my problem..
we are doing FTP (one report out put) from one server to another server through unix shell script program.
Due to the network issues, some times FTP process is hanging.
So we planned to modify the existing program with the following... (2 Replies)
Dear All,
i want to implement vookup function which is there in excel into Unix. Suppose i have 2 files. The files are given below.
File1:
MSC Cell SDCA
Patna-1 12 Bihar
Patna-2 45 Ranchi
Bhopal-1 85 Raigarh
Bhopal-2 ... (8 Replies)
hi,
i am having three files which is having following data
file1:
field1 field2 field3
1 A B
2 C D
3 E F
file2:
4 G H
1 I J
5 K L
file3:
4 M N (3 Replies)
Hello, could anybody explain how the ps command works? I know something about the proc file system. But I'm still not sure about how it exactly works. Like ps without any option will print out the current user's processes, but it never displays my web browsers such as firefox or my LibreOffice... (3 Replies)
Hello, I'm currently implementing the && function in a shell using C. For example, if we input cmd1 && cmd2, then cmd2 executes only when cmd1 exits successfully. I'm thinking about:
int main() {
int i;
char **args;
while(1) {
printf("yongfeng's shell:~$ ");
args =... (5 Replies)
Discussion started by: Yongfeng
5 Replies
LEARN ABOUT CENTOS
shell-quote
SHELL-QUOTE(1) User Contributed Perl Documentation SHELL-QUOTE(1)NAME
shell-quote - quote arguments for safe use, unmodified in a shell command
SYNOPSIS
shell-quote [switch]... arg...
DESCRIPTION
shell-quote lets you pass arbitrary strings through the shell so that they won't be changed by the shell. This lets you process commands
or files with embedded white space or shell globbing characters safely. Here are a few examples.
EXAMPLES
ssh preserving args
When running a remote command with ssh, ssh doesn't preserve the separate arguments it receives. It just joins them with spaces and
passes them to "$SHELL -c". This doesn't work as intended:
ssh host touch 'hi there' # fails
It creates 2 files, hi and there. Instead, do this:
cmd=`shell-quote touch 'hi there'`
ssh host "$cmd"
This gives you just 1 file, hi there.
process find output
It's not ordinarily possible to process an arbitrary list of files output by find with a shell script. Anything you put in $IFS to
split up the output could legitimately be in a file's name. Here's how you can do it using shell-quote:
eval set -- `find -type f -print0 | xargs -0 shell-quote --`
debug shell scripts
shell-quote is better than echo for debugging shell scripts.
debug() {
[ -z "$debug" ] || shell-quote "debug:" "$@"
}
With echo you can't tell the difference between "debug 'foo bar'" and "debug foo bar", but with shell-quote you can.
save a command for later
shell-quote can be used to build up a shell command to run later. Say you want the user to be able to give you switches for a command
you're going to run. If you don't want the switches to be re-evaluated by the shell (which is usually a good idea, else there are
things the user can't pass through), you can do something like this:
user_switches=
while [ $# != 0 ]
do
case x$1 in
x--pass-through)
[ $# -gt 1 ] || die "need an argument for $1"
user_switches="$user_switches "`shell-quote -- "$2"`
shift;;
# process other switches
esac
shift
done
# later
eval "shell-quote some-command $user_switches my args"
OPTIONS --debug
Turn debugging on.
--help
Show the usage message and die.
--version
Show the version number and exit.
AVAILABILITY
The code is licensed under the GNU GPL. Check http://www.argon.org/~roderick/ or CPAN for updated versions.
AUTHOR
Roderick Schertler <roderick@argon.org>
perl v5.16.3 2010-06-11 SHELL-QUOTE(1)