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:
But It's not very clear pratically. Surfing on the net I've found just hard examples.
Can anyone help with a small example that show how can i use the times function?
Dear Friends,
I write a c program to list the directories recursively. For this I write a function called my_readdir to read the content of directory. For this I use read system call it returns -1, then I use readdir system call it gives comment terminated error or segmentation... (1 Reply)
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)
I have a cgi script which is called after certain time interval, which has this:
system ("ls -l /tmp/cgic* | grep -v \"cgicsave.env\" | awk '{print $5}'");
During the execution of this script,the output is 0 sometimes. But due to this the system call is not working at all and doesnt o/p... (2 Replies)
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)
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)
Hi again ;) Now I want to make a program that will execute the programs with exec, asking the user if he wants the program to run in background or foreground.
scanf("%c",&caracter);
if (caracter=='y'){
printf("Has decidido ejecutarlo en background\n");
if((pid=fork())==0) {// fork para... (3 Replies)
newPerm = oldPerm & ~0100;
where oldPerm holds the value of st_mode from the system call stat().
When I try and compile every line where ive attempted to do these operations gives the warning "parameter names without declaration types in function declaration". what could be the problem? the... (2 Replies)
Discussion started by: bjhum33
2 Replies
LEARN ABOUT HPUX
clock_getres
clocks(2) System Calls Manual clocks(2)NAME
clock_settime(), clock_gettime(), clock_getres() - clock operations
SYNOPSIS DESCRIPTION
clock_settime()
The function sets the specified clock, to the value specified by Time values that are between two consecutive non-negative integer multi-
ples of the resolution of the specified clock are truncated down to the smaller multiple of the resolution.
clock_gettime()
The function returns the current value for the specified clock,
clock_getres()
The resolution of any clock can be obtained by calling Clock resolutions are implementation defined and are not settable by a process. If
the argument is not NULL, the resolution of the specified clock is stored into the location pointed to by If is NULL, the clock resolution
is not returned.
A clock may be system wide, that is, visible to all processes; or per-process, measuring time that is meaningful only within a process.
The following clocks are supported:
This clock represents the realtime clock for the system.
For this clock, the values returned by and specified by represent the amount of time (in seconds and nanoseconds) since
the Epoch. It is a system wide clock. The privilege is required to set this clock. Processes owned by the superuser
have this privilege. Processes owned by other users may have this privilege, depending on system configuration. See
privileges(5) for more information about privileged access on systems that support fine-grained privileges.
This clock represents the amount of time (in seconds and nanoseconds)
that the calling process has spent executing code in the user's context. It is a per-process clock. It cannot be set
by the user.
This clock represents the amount of time (in seconds and nanoseconds)
that the calling process has spent executing code in both the user's context and in the operating system on behalf of
the calling process. It is a per-process clock. It cannot be set by the user.
These clocks are high resolution hardware clocks
present on HP-RT realtime systems. It is included here so that applications accessing this hardware can be compiled on
HP-UX systems and then ported to an HP-RT target. HP-UX does not support or
RETURN VALUE
A return of zero indicates that the call succeeded. A return value of -1 indicates that an error occurred, and is set to indicate the
error.
ERRORS
If any of the following conditions occur, the and functions return -1 and set (see errno(2)) to the corresponding value:
The functions
and are not supported by this implementation.
The argument does not specify a known clock.
The argument to is outside the range for the given
The argument specified a nanosecond value less than zero or greater than or equal to 1000 million.
The requesting process does not have the necessary privileges to set the
specified clock.
The or argument points to an invalid address.
EXAMPLES
Advance the system wide realtime clock approximately one hour:
Get the resolution of the user profiling clock:
AUTHOR
and were derived from the proposed IEEE POSIX P1003.4 Standard, Draft 14.
SEE ALSO timers(2), privileges(5).
STANDARDS CONFORMANCE clocks(2)