10-21-2008
System call code - nice()
Hi there, i'm trying to find the implementation code for the system call nice().
Since it's a system call i'm having problems finding where it would be? is it in the linux kernel directory somewhere?
I would assume it would be a file called nice.c or something like this.
Thanks in advance!
10 More Discussions You Might Find Interesting
1. UNIX for Dummies Questions & Answers
Can someone tell me this. thanks (1 Reply)
Discussion started by: xoxouu
1 Replies
2. Programming
Hi I want to implement the nice command in the shell that I am building. I came to know that there is a corresponding nice() system call for the same. But since I will be forking different processes to run different commands typed on the command prompt, is there any way I can make a command... (2 Replies)
Discussion started by: tejbuch
2 Replies
3. UNIX for Advanced & Expert Users
Hi,
Ho do I differentiate system call from library call?
for example if I am using chmod , how do I find out if it is a system call or library call?
Thanks
Muru (2 Replies)
Discussion started by: muru
2 Replies
4. Programming
How the c compiler differentiates the system calls and function calls? (1 Reply)
Discussion started by: rangaswamy
1 Replies
5. Programming
Hi,
1. Can anybode suggest me where to find the source code for system calls itself? Like open(), read(), close(). May I have the link or book where I can find the source code these functions itself?
2. When ever we quit a file or save and quit a file, the file content is stored in the disk.... (6 Replies)
Discussion started by: ramkrix
6 Replies
6. Shell Programming and Scripting
Hi,
How to write a system calls in a script ?
> cd $HOME
> ls -ltr
thanks in advance.. (10 Replies)
Discussion started by: hegdeshashi
10 Replies
7. Programming
Hi
I'm studing the system call. I've written a small program that return the time spent in doing some operations. Now I'd like to write one that return the time spent in user mode of a process.
I'm reading that i should use the tms struct:
clock_t times(struct tms *buf);
struct tms {... (2 Replies)
Discussion started by: Dedalus
2 Replies
8. Shell Programming and Scripting
Hello,
I am just starting with shell scripting, as everyone will soon see from my question. What I'm trying to do is call the Nice command to set the script process priority from /bin/ksh. The difference is I'm running it not directly through the shell, but through Bigfix (very similar to... (3 Replies)
Discussion started by: solly119
3 Replies
9. Programming
hi everyone
i wrote a system call and compiled the kernel succesfully...
my system call is in a file in the kernel folder named my_syscall1.c (kernel/my_syscall1.c)
the header file for this system call i added it in the folder include like this include/my_syscall1/my_syscall1.h
my problem is... (2 Replies)
Discussion started by: demis87
2 Replies
10. Shell Programming and Scripting
Trying to figure out a load issue with a webserver. I have traced a php script and noticed the following
connect(4, {sa_family=AF_INET, sin_port=htons(3306), sin_addr=inet_addr("XX.XX.XX.XX")}, 16) = -1 EINPROGRESS (Operation now in progress) <0.000035>
poll(, 1, 2000) = 1 () <0.000120>... (5 Replies)
Discussion started by: rajan007
5 Replies
nice(2) System Calls nice(2)
NAME
nice - change priority of a process
SYNOPSIS
#include <unistd.h>
int nice(int incr);
DESCRIPTION
The nice() function allows a process to change its priority. The invoking process must be in a scheduling class that supports the nice().
The nice() function adds the value of incr to the nice value of the calling process. A process's nice value is a non-negative number for
which a greater positive value results in lower CPU priority.
A maximum nice value of (2 * NZERO) -1 and a minimum nice value of 0 are imposed by the system. NZERO is defined in <limits.h> with a
default value of 20. Requests for values above or below these limits result in the nice value being set to the corresponding limit. A nice
value of 40 is treated as 39.
Calling the nice() function has no effect on the priority of processes or threads with policy SCHED_FIFO or SCHED_RR.
Only a process with the {PRIV_PROC_PRIOCNTL} privilege can lower the nice value.
RETURN VALUES
Upon successful completion, nice() returns the new nice value minus NZERO. Otherwise, -1 is returned, the process's nice value is not
changed, and errno is set to indicate the error.
ERRORS
The nice() function will fail if:
EINVAL The nice() function is called by a process in a scheduling class other than time-sharing or fixed-priority.
EPERM The incr argument is negative or greater than 40 and the {PRIV_PROC_PRIOCNTL} privilege is not asserted in the effective set of
the calling process.
USAGE
The priocntl(2) function is a more general interface to scheduler functions.
Since -1 is a permissible return value in a successful situation, an application wishing to check for error situations should set errno to
0, then call nice(), and if it returns -1, check to see if errno is non-zero.
ATTRIBUTES
See attributes(5) for descriptions of the following attributes:
+-----------------------------+-----------------------------+
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+-----------------------------+-----------------------------+
|Interface Stability |Standard |
+-----------------------------+-----------------------------+
|MT-Level |Async-Signal-Safe |
+-----------------------------+-----------------------------+
SEE ALSO
nice(1), exec(2), priocntl(2), getpriority(3C), attributes(5), privileges(5), standards(5)
SunOS 5.10 1 Apr 2004 nice(2)