Why are you opening and closing the file every time you do something?
This especially becomes useless:
...because the seek position gets reset every time you open it anyway. You should open it once and keep using the number it gives you. Your read code would end up looking like int readFromDisk(int fd, char *buffer,int length) { ... } iow exactly like normal read...so you might as well get used to ordinary read call instead.
You should also be doing something more with the number of bytes written and read than just printing it. read() and write() will occasionally surprise you with less than you asked for.
Hi all
I am facing a strange problem.
I am using a sun ultra10 spark machine.
first i took a 20gb IDE hard disk and installed solaris 5.8.
But due to some requirement i have to reinstall the OS but this time solaris 2.6.
and now the hard disk capacity is only showing 8gb.
Where the 12gb... (3 Replies)
I had an issue with a second hard disk in my machine. I have a sparc station running solaris 7. It was working fine but now it wont mount on boot up and when you try to mount it manually it gives an I/O error. I tried a different disk as a control which was fine. What I want to know is if my... (3 Replies)
:eek: I use this Solaris to run CMS a call acounting software package for my job. No one could run reports today because it said the this when you logged on
"The following file systems are low, and could adversely affect server performance:
File system /: 99%full"
Can some one please explain... (9 Replies)
Hi guys i have created a linux machine in virtual box now i want to add some hard disk space into it.
How would i do this.
Please help.
Machine details are as below
# lsb_release -a
LSB Version: :core-3.1-ia32:core-3.1-noarch:graphics-3.1-ia32:graphics-3.1-noarch
Distributor ID:... (7 Replies)
hi
I've a fresh installation of SCO 5.0.7 on the IDE hard disk.
For SCSI hard disk I can declare, for example blc disk driver using:
# mkdev hd 0 SCSI-0 0 blc 0but it works for IDE hard disk? (3 Replies)
When we write a programme,we declare variables and compiler allocates memory to them.I want to get access to the physical block number of hard-disk where actually the data is stored by the programme "
Some one help me out... (1 Reply)
When we write a programme,we declare variables and compiler allocates memory to them.I want to get access to the physical block number of hard-disk where actually the data is stored by the programme "
Some one help me out... (3 Replies)
Discussion started by: nagraz007
3 Replies
LEARN ABOUT LINUX
set_tid_address
SET_TID_ADDRESS(2) Linux Programmer's Manual SET_TID_ADDRESS(2)NAME
set_tid_address - set pointer to thread ID
SYNOPSIS
#include <linux/unistd.h>
long set_tid_address(int *tidptr);
DESCRIPTION
The kernel keeps for each process two values called set_child_tid and clear_child_tid that are NULL by default.
set_child_tid
If a process is started using clone(2) with the CLONE_CHILD_SETTID flag, set_child_tid is set to child_tidptr, the fifth argument of that
system call.
When set_child_tid is set, the very first thing the new process does is writing its PID at this address.
clear_child_tid
If a process is started using clone(2) with the CLONE_CHILD_CLEARTID flag, clear_child_tid is set to child_tidptr, the fifth argument of
that system call.
The system call set_tid_address() sets the clear_child_tid value for the calling process to tidptr.
When clear_child_tid is set, and the process exits, and the process was sharing memory with other processes or threads, then 0 is written
at this address, and a futex(child_tidptr, FUTEX_WAKE, 1, NULL, NULL, 0); call is done. (That is, wake a single process waiting on this
futex.) Errors are ignored.
RETURN VALUE
set_tid_address() always returns the PID of the calling process.
ERRORS
set_tid_address() always succeeds.
VERSIONS
This call is present since Linux 2.5.48. Details as given here are valid since Linux 2.5.49.
CONFORMING TO
This system call is Linux-specific.
SEE ALSO clone(2), futex(2)COLOPHON
This page is part of release 3.27 of the Linux man-pages project. A description of the project, and information about reporting bugs, can
be found at http://www.kernel.org/doc/man-pages/.
Linux 2004-09-10 SET_TID_ADDRESS(2)