The value assigned to $! is the process id of the last command started in the background from the current shell.
It can be useful if you want to do something like this:-
Whilst the copy is running, the user will get a row of dots growing by one each second. It makes them think something is happening when they see a display moving. It can be a useful filler to stop them cancelling mid-way. I've fixed a few 'intermittent' problems with just such a placebo.
Of course, you could have a more processing efficient action to take and it allows a little bit of multi-threading of your script, or you can have a script that starts various sub-processes and you could collect the process id from each, then periodically check that they are still running.
I hope that this explains a little. Feel free to ask more.
question: for the below program
i just printed the value for pid, child pid and parent pid
why does it give me 6 values? i assume ppid is 28086
but can't figure out why there are 5 values printed instead of just two!
can someone comment on that!
#include<stdio.h>
#define DIM 8
int... (3 Replies)
The below command returns full line.How can i get only PID from this line ie 15794 from the below example
(FI NY) nbswpsa52.ny.ficc.gs.com~ ->ps -ef | grep keepalive | grep -v keepaliveStub | grep -v swapback | grep -v grep
ficctprd 15794 1 0 13:12:58 ? 0:01 keepalive (3 Replies)
Hi ,
I am trying to get the PID using the following command:
$ /usr/ucb/ps -auwwwwx | grep java | grep Proceess | ptree PID or
$ /usr/ucb/ps -auwwwwx | grep java | grep Proceess;ptree PID
it is possible to get PID, such that I check whether any orphan
process is running.
solution... (0 Replies)
1. If I use an software application(which connects to the database in the server) in my local pc, how many PID should be registered? Would there be PID for the session and another PID for socket connection?
2. I noticed (through netstat) that when I logged in using the my software application,... (1 Reply)
Hi All,
In my project i have two process runs in the back end.
Once i start my project, and execute the command ps, i get below output:
PID TTY TIME CMD
9086 pts/1 0:00 ksh
9241 pts/1 0:02 java
9240 pts/1 0:00 shell_script_bg
java with 9241 PID is the main... (4 Replies)
Hi,
I need to get the pid of a process and have to store the pid in a variable and i want to use this value(pid) of the variable for some process. Please can anyone tell me how to get the pid of a process and store it in a variable. please help me on this.
Thanks in advance,
Amudha (7 Replies)
Hello people,
This question might seem to be a little naive but here it goes:
I want to know the PID of a script that is running in the background.
eg: There is a script called Data_Downloader.sh
I am using the command:
ps -ef | grep Data_Downloader.sh
But I am getting the output as
wrkarea... (9 Replies)
I have searched to find an anwer to no avail, I hope you can help me.
I have a.ksh that many people call and a.ksh calls b.ksh
b.ksh is also invoked stand-alone by many people as well
In b.ksh I want to do something different if it was not involked by a.ksh.
How can I do this? (7 Replies)
name the process wit PID value 0? swapper or scheduler or both.... (3 Replies)
Discussion started by: karthi_g
3 Replies
LEARN ABOUT OPENDARWIN
script
SCRIPT(1) BSD General Commands Manual SCRIPT(1)NAME
script -- make typescript of terminal session
SYNOPSIS
script [-a] [-k] [-q] [-t time] [file [command ...]]
DESCRIPTION
The script utility makes a typescript of everything printed on your terminal. It is useful for students who need a hardcopy record of an
interactive session as proof of an assignment, as the typescript file can be printed out later with lpr(1).
If the argument file is given, script saves all dialogue in file. If no file name is given, the typescript is saved in the file typescript.
If the argument command ... is given, script will run the specified command with an optional argument vector instead of an interactive shell.
Options:
-a Append the output to file or typescript, retaining the prior contents.
-k Log keys sent to program as well as output.
-q Run in quiet mode, omit the start and stop status messages.
-t time Specify time interval between flushing script output file. A value of 0 causes script to flush for every character I/O event. The
default interval is 30 seconds.
The script ends when the forked shell (or command) exits (a control-D to exit the Bourne shell (sh(1)), and exit, logout or control-d (if
ignoreeof is not set) for the C-shell, csh(1)).
Certain interactive commands, such as vi(1), create garbage in the typescript file. The script utility works best with commands that do not
manipulate the screen. The results are meant to emulate a hardcopy terminal, not an addressable one.
ENVIRONMENT
The following environment variable is utilized by script:
SHELL If the variable SHELL exists, the shell forked by script will be that shell. If SHELL is not set, the Bourne shell is assumed. (Most
shells set this variable automatically).
SEE ALSO csh(1) (for the history mechanism).
HISTORY
The script command appeared in 3.0BSD.
BUGS
The script utility places everything in the log file, including linefeeds and backspaces. This is not what the naive user expects.
It is not possible to specify a command without also naming the script file because of argument parsing compatibility issues.
When running in -k mode, echo cancelling is far from ideal. The slave terminal mode is checked for ECHO mode to check when to avoid manual
echo logging. This does not work when in a raw mode where the program being run is doing manual echo.
BSD June 6, 1993 BSD