09-23-2008
locking mechanism
I have a shell script.
How can use some kind of locking mechanism to ensure that the script is not being executed by two people
at the same time?
8 More Discussions You Might Find Interesting
1. Programming
Hi,
The description and the context of the mechanism that i require is as follows:
There is an application communicating with a protocol stack binary. There is a TCP socket communication between the two.
Now, the stack is pumping up data to the Application such that the receiving buffer of... (2 Replies)
Discussion started by: saptarshi
2 Replies
2. UNIX for Dummies Questions & Answers
Hi all,
Like in windows OS we have in unix something called "jobs"-term me if i am wrong- to run a sequence of steps which we can exceute at our own will without scheduling like corntab scheduling. can any one tell me what is the structure of this file and provide me with some info with this... (5 Replies)
Discussion started by: aixjadoo
5 Replies
3. AIX
Hi all,
on aix,whether have udev or devfs mechanism?
thanks! (4 Replies)
Discussion started by: anonys
4 Replies
4. Solaris
hi,
I have some windows client machines which require a signal to be sent by a Solaris machine( SunOS 5.6) when ever a particular event occurs on that Solaris machine. What are possible communication mechanisms by which i can do this.
the constraints are
> the windows machines have to... (7 Replies)
Discussion started by: Krsh
7 Replies
5. Programming
OIOIC is a completely new object-oriented mechanism for the C programming language.
Please download the "OIOIC-Primer-2nd-Edition-English.tar.gz". (the English version of << OIOIC Primer >> )
http://code.google.com/p/oioic/downloads/list
Welcome your advice!
Using OIOIC, you can describe... (7 Replies)
Discussion started by: pervise.zhao
7 Replies
6. Shell Programming and Scripting
Hello Folks,
I got an issue to be solved. I need to show the user a progress bar while executing an process using shell script
Example:
While updating firmware lets assume this will take 2 min to upgrade i need the shell script to show the progress bar as (0%) and at the end it should... (13 Replies)
Discussion started by: phanivarma
13 Replies
7. Shell Programming and Scripting
What if the operating systems would not use any ipc mechanism in order to exchange the datas with each other,which technique could be an alternative for messaging between the processes?Do you guys think using the vfork () system call to duplicate processes is a logical solution for this problem? (4 Replies)
Discussion started by: helltrex
4 Replies
8. Programming
Suppose I have 5 independent process divided in two imaginay sets:
set1 set2
---------------------
p1 p3
| |
p2 p4
|
p5
The processes inside each set communicate mutually quite often.
I mean p1 and p2 communicate mutually quite often
Similarly p3, p4 and p5 communicate mutually... (2 Replies)
Discussion started by: rupeshkp728
2 Replies
chsh(1) General Commands Manual chsh(1)
NAME
chsh - change default login shell
SYNOPSIS
login-name [shell]
login-name [shell]
login-name [shell]
login-name [shell]
DESCRIPTION
The command changes the login-shell for a user's login name in the repository (see passwd(1)).
The DCE repository is only available if Integrated Login has been configured; see auth.adm(1M). If Integrated Login has been configured,
other considerations apply. A user with appropriate DCE privileges is capable of modifying a user's shell; this is not dependent upon
superuser privileges.
If the repository is not specified (as in [login-name]), the login shell is changed in the file only.
Run after running to make sure the information was processed correctly.
Notes
The command is a hard link to the command. When is executed, actually the command gets executed with appropriate arguments to change the
user login shell in the repository specified in command line. If no repository is specified, the login shell is changed in the file.
Arguments
login-name A login name of a user.
shell The absolute path name of a shell. If the file exists, the new login shell must be listed in that file. Otherwise, you
can specify one of the standard shells listed in the getusershell(3C) manual entry. If shell is omitted, it defaults to
the POSIX shell,
Options
The following option is recognized:
Specify the repository to which the operation is to be applied.
Supported repositories include and
Security Restrictions
You must have appropriate privileges to use the optional login-name argument to change another user's login shell.
NETWORKING FEATURES
NFS
File can be implemented as a Network Information Service (NIS) database.
EXAMPLES
To change the login shell for user to the default:
To change the login shell for user to the C shell:
To change the login shell for user to the Korn shell in the DCE registry:
WARNINGS
If two or more users try to write the file at the same time, a passwd locking mechanism was devised. If this locking fails after subse-
quent retrying, terminates.
AUTHOR
was developed by HP and the University of California, Berkeley.
FILES
SEE ALSO
chfn(1), csh(1), ksh(1), passwd(1), sh(1), sh-posix(1), getusershell(3C), pam(3), passwd(4), shells(4).
chsh(1)