I am using pthread_create system call to create a thread. However pthread_create does not return the PID ( process ID). Is there any quick way to fınd the PID of the created thread.
View 1 RepliesI am want get next information: Get process statistics from kernel and return them buf as
Quote:
number of processes : ticks_user : ticks_system : ticks_interrupt : cpuseconds : procsizes : resident segment sizes I am find some this information in /proc/[pid]/stat, but there are is not data about ticks system, ticks_interrupt, cpusecond. Where I am can find it information???
I am write on C, better if it will file witch information, and not programm.
Is it possible to have an Expect script spawn an SSH session, log in, then go into interactive mode and give control of the SSH session to a Bash script? Here's a simplified example of the script so far:
Code:
#!/bin/bash
expect -c "
[code]....
I am having trouble linking the pthread library.I have -lpthread -lm as options for the GNU GCC compiler.
Build Log
Compiling: main.c
Compiling: matrix.c
[code]...
each time my linux is booting, it check something like eth0 and something else. but there is something i write below that fail... Code: could not receive return value from daemon proccess?
View 3 Replies View RelatedI have a script in /etc/rc.d/init.d named foo. I want to start/stop/restart my process as follows:$ foo start But I do not see the [OK] message once it starts. There is no shell prompt returned either. It seems that my own process is the problem. The executable that foo calls is built from this sample code:
int main()
{
do {
printf("Hello world
");
sleep(1);
} while (1);
}
Do I have to return some kind of signal handle for this to work?
my code is very simple:
int pid, status;
printf("parent process id=%d, to call fork
",getpid());
if(pid=fork()<0)
[Code].....
but everytime I can only get two fork return pid=0. In parent process, the pid returned by fork() should be >0 and equal to the child process id.
I trying to write a UART(interfacing of serial devices) to linux machine but after I execute the following code to receive data I need to enter key (carriage return).... but I don't want to remove carriage return/enter key
[Code]....
I have a shell script to identify whether the process is running or not. If the process is not running, then I execute another script file to run my application. Below is my script and saved this script as monitorprocess.sh Code: #!/bin/bash
result=$(ps -ef | grep -v grep | grep "applicationname.sh" | awk '{print $2}')
echo $result
if [ "$result" == "" ];
[code]...
Is there any difference in cpu usage for process in init.rc(runs automatic when boot is happened) and manually running process. Will these both have same priority by default...?
View 1 Replies View RelatedI tried googling but didn't get any answer for this.I have a process called "abc" and it is running with PID "123".I have a putty session opened with PID "999".I am giving kill -TERM 123 from putty session.My process "abc" before dying it should catch the PID of the terminal which provided TERM signal to it.Is there any way to find this out
View 2 Replies View Relatedi am having two small issues with a function i have made.sorry if it is a mess, i am still learning bash.the first is calling the nonpersistssh function (second line) and assigning the return value to nonpersistdiag.the function returns 1, but nonpersistdiag seems to only contain 0. i am unsure on how to proceed.the second problem is the nested else clause on line 10. it is a syntactical error. how would i declare it correctly?
Code: function endsession(){
nonpersistdiag=$[nonpersistssh]# a function that returns an exit code
sudo /etc/init.d/ssh stop; sshdiag=$?
[code]....
What are the uses of return 0, return 1 and exit statements in C
View 4 Replies View RelatedOn this link [URL]4 a return type is defined
Code:
return ((unsigned int)(unsigned long)base & TBASE_DEFERRABLE_FLAG);
What is the above function returning.I am not clear with definition of what is being returned in the above code.
I'm confused about what "echo $0" in a shell actually return. Consider these tests:
Code:
[root@e11apvl151 ~]# # Login shell:
[root@e11apvl151 ~]# echo $0
-bash
[root@e11apvl151 ~]# # Starting a new shell
[root@e11apvl151 ~]# bash
[root@e11apvl151 ~]# echo $0
bash
[root@e11apvl151 ~]# screen
[root@e11apvl151 ~]# echo $0
/bin/bash
Depending on wether the shell is a login shell, a regular shell, or a screen utility, I get different results.
I have a file:
979798707
787862348
766428634
I want to see if all the records in the file are present in the contents of the files of a particular directory.
Basically I want to say if grep doesn't return anything, then report.
For example in /tmp dir I have 4 files and flast 2 values (787862348 and 766428634) are present in the files of /tmp dir, but first one (979798707) is not. I want to echo that in a reporting file.
something like:
while read line
do
# if ! grep -rl $line /tmp
echo $line >> are_not_present
done < "myFile"
How do I achieve " if ! grep -rl $line /tmp"? That is, if the line is found by grep, then grep will print the output, but if grep does'nt find it, it will print nothing. How can I check if grep didn't find it (i.e. printed nothing)?
I'm reading a text file with fscanf using a loop until feof(inFile). How can I return to the top of the file? As in I have one loop that scans until the eof and then after it there's another loop and I want to start from the beginning of the file again scanning to the end of it. How do I get back there?
View 3 Replies View RelatedI am testing the serial ports on a Single Board Computer(SBC) running Linux kernel 2.6.29. I usually do this by connecting the serial port to another PC serial port, then doing "cat /dev/ttyS0" on PC and "echo hello > /dev/ttyS0" on the SBC. However in the current system, "echo hello > /dev/ttyS0" command does not return at all! Also no characters appear on the destination port. I am running the echo command as root. The system boot messages show that the serial port in indeed /dev/ttyS0.
View 2 Replies View RelatedI think my title pretty much explains it. I am writing a script and I want to start a program in the background, and when that program finishes I want to check the return value to make sure there was no error.For example normal I would do something like this:
#!/bin/sh
program
if [ ! $? -eq 0 ]; then
echo "There was an error"
exit 1
fi
Now I want to do something like this:
#!/bin/sh
PRTN=`program1 &`
program2
if [ ! $? -eq 0 ]; then
[code]....
In this case if program2 finishes before program1, I don't think the return value from program1 $PRTN would be valid at the time it is checked.
C++ code:
Code:
#include<fstream.h>
[code]....
I write a little script by bash.
#!/bin/bash
a=`gawk '/Iterations /{print $0}' hoge.log | gawk 'BEGIN{FS=" "}{print ($4)}'`
a=`expr 3 '*' $a`
[code]...
I have always encountered this problem in ubuntu bash shell scripts that echo command in a function will be treated as a return value when used in a function. e.g.
[code]...
The output would simply be xyz. Hence the echo seems to function as a "return" command when used in a function with a return value.
$val = mkdir $directory, 755
print $val;
does't create directory but return as value '0'
[code]....
I have confusion regarding pthreads return value. All in short, is the is a valid return value ?
[source]
void * myThrRoutine(void *arg)
{
struct myStruct **myst = (struct myStruct**) arg;
cout<<"In thread "<<(*myst)->var<<(*myst)->msg<<endl;
int x = 20;
pthread_exit((void*)x);
}
[/source]
This seems to work fine on pthread_join , but I want to ensure it is not by chance.
But it's been hell finding an answer, or I just don't know what to look for..I have a prompt that asks for a float, and if the user doesn't put in a valid number, then it should die with an error message.
Code:
def die_with_error():
print 'ERROR: You didn't specify a valid number!'
[code]....
when i install bochs and make the makefile why undefined reference to `pthread_create'
View 1 Replies View RelatedI am using Gstreamer for creating one of my video streaming application. My application creates multimedia session and then stream around 200 video sessions (a very processor intensive job).In doing so, the no. of threads created is around 1500 and I have given around 1536 KB as my stack size for each of these threads. I have one Quadcore(intel Xeon) system of around 8 GB of RAM(64 bit) with RHEL 5.5(kernel - 2.6.18-92.el5). After few hours of testing I see that my overall memory(RAM) is eating up. I did checked the memory and I saw that my cache size is growing. So far so good, as I can understand that system does cache instead of leaving some RAM free.
My problem comes, when I see that after almost 20-25 hours of testing, RAM is continuously being eaten up and maximum part of that is going into cache. If I leave the system for few more hours I see whole of my memory is consumed up and now my swap started getting used. If I check the cache now, I clearly see most of RAM is now in form of cache. I still didn�t stop my application and allowed it run for few more hours and after sometime I see that process give segmentation fault while creating the pthread (create_pthread::unknown error 513).I also tried to observe the �core� file of application created in this way , but it doesn�t� show anything.
One thing I must mention that, in �top� I see almost constant values of resident memory, virtual memory and shared memory. There is no increase of memory usage here. So here I can assume that my application is not leaking the memory. I also observed that if I kill my application any time during this, the memory doesn�t go into free pool. Anyone, here can give any pointer for this kind of behavior. Is it can be because of some kernel BUG which is not freeing the memory to application usage.
I have an a script in /etc/rc.d/init.d script that I would like to start and stop my sample application. I have named my script "foo", then I can start running my application my typing $ foo start but this does not return [OK] like other scripts do and does not return to shell prompt. My application is basically like this
int main()
{
do {
printf("Hi
");
sleep(1);
} while (1);
}
What is missing from my application that prevents from returning the shell prompt?
I'm getting some information about C language and this session of a C book (follow the above link) is using a bad example for me. When I'm trying this example of function returning a pointer, my compiler is stating a warning that I return a pointer to a local variable. I realized that it is error prone after all this variable may be override before the function has done his execution. And the author is fooling me saying that this example is "perfectly safe". I'm wrong? There is something that I don't got yet? Sorry but this site is preventing me to post the link of book cause I'm a newbie, so a need the hack it. Just strip out the question signs:
{LINK}
?w?w?w
?cs.cf.ac.uk?
[code]....
I have functions which return different data like: int, char*, double...
I also have a list of datatypes (INTEGER, TEXT, REAL...) which can be returned.
I need to map a datatype with function, which purpose is to return it. Therefore, when I determine a datatype, I would like to call the required function without doing switch all the time.
My idea is to have an array of structs like this:
Code:
struct type_func_map
{
int type;
void (*func_wrapper_int)(void); //void (*func_wrapper_text)(void); void (*func_wrapper_real)(void);
};
[Code].....