On 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.
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]....
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'm trying to teach myself python (from Learn Python the hardway e-book) but am struggling to grasp the concepts of Classes etc. Part of exercise 43 is to rewrite the game / create a new game with classes for each room etc. So I'll show you my code so far and explain at the bottom my problem
Code:
#ex43a.py
from sys import exit
[code]....
I have a script that i want to add some functionality to, but im new to python. Right now it runs command line as ./script https://server user passwd verbose , which returns alot of informtion. I would like it to be able to only return information for a particular function when a flag is passed. exp: ./script https://server user passwd verbose -m (for memory only)
Under the ClassesToCheck section are the different things that can be retrieved. I would like that when you run the script as ./script https://server user passwd verbose -m, it returns only the 'Memory' info. -c would be for 'CPU', etc... Also, i would like the OK at the end of the script to be the first line that is return in the output instead of the last.
I'm trying to write some code that involves creating a function to return a vector iterator.I'm not sure what is wrong.
Code:
template <typename T> class VectorTemplate
{
[code]....
I need to make a function combination to get for: If cell A1 then for B1 as:
A1 B1
--- ---
abc abc
hello hello
empty empty
0 0
-3 -3
5 5
and like wise
Code:
#include <iostream>
using namespace std;
[code]...
I am doing some Linux kernel programming for my research project. I need to record the timestamp (by using cpuid and rdtsc) when an interrupt handler (top half) is first invoked. Due to the time critical nature of the problem itself, I have to do the timestamping inside the interrupt handler itself (the first operation when the handler is called). However, I understand that tasks that are not so time critical should be deferred to a tasklet function (bottom half) for processing because other interrupts are disabled in a (top-half) interrupt handler. I am currently out of idea on how I can pass the timestamp information that I have obtained in the interrupt handler to the corresponding tasklet function.
View 2 Replies View RelatedI want to declare a function in a function, but had no success till now, see the error code below and visit the project at sourceforge
[Code]...
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 looked on the net for such function or example and didin't find anything, thus after having made one i guess it would be legitimate to drop it to see what others thinks of it.
#!/bin/bash
addelementtoarray()
{
local arrayname=$1
[code]....
i am having two small issues with a function i have made.sorry if it is a mess, i am still learning bash.the first is calling the nonpersistssh function (second line) and assigning the return value to nonpersistdiag.the function returns 1, but nonpersistdiag seems to only contain 0. i am unsure on how to proceed.the second problem is the nested else clause on line 10. it is a syntactical error. how would i declare it correctly?
Code: function endsession(){
nonpersistdiag=$[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 RelatedI'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.
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 Replies View RelatedC++ 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.
fit a surface i.e. W(x,y) using svdfit() provided by "Numerical Recipes in C". svdfit() is written for curve fitting and not for surface fitting.But one can use svdfit(), as claimed by authors of NR book, to do surface fitting. On page 680 of NR book, authors have given a hint on how to use svdfit() for fitting a surface. But I have not understood it.This link may be helpful (Chapter 15 th is relevant here.):[URL]This is my problem:
Code:
I have a set of 100 numbers. I want to fit a 2-Dimensional function W(x,y) to these numbers.
[code]....
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 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].....
I have a script that reads part of a line, delimited between the first and second intended part by a colon. Then it "chops" the part after the colon, which are words offset by commas (counting them beforehand so as to catch every word in the string's second part), like this:
Code:
"COLORS.JPG:red,orange,yellow,green,"
(Returning)
red
[code]....
single script that parses/breaks both parts of a line like this "COLORS.JPG:red,orange,yellow,green;blue,indigo,violet," so that the two parts, separated into single words (or two and three words, sometimes with spaces) can be used as single-line annotations and written to JPEG files using Exiv2. So far, I haven't been able to come up with a script that does this without one part of the total string(usually that part after the colon) becoming the first word in the second array. In other words, I look for this:
KEYWORDS:
[ ]red
[ ]orange
[ ]yellow
[code]....
Or vice-versa (ie, the second array winds up as a single-line "member" of the first). I think it's because I'm using a single while read loop to read the text file in which the filenames and substrings happen to be. If there's some way of reading a file once and going back to the beginning to read it again in another while loop, I haven't found it.
I have a function that returns a boolean value, True of False. Is there any convention whether 0 = False or 0 = True? It should be obvious, 0=False, 1=True. However programs usually return 0 on success and reserve higher numbers for error values. I.e. if the program finishes successfully (function int main() finishes successfully ), it returns 0 - and that contradicts that 0 should be false.
And especially if I want a function to do some computations on parameters passed by reference and return success status. Should it return 1 (true) for success, or should it return 0 for success - like any Unix program does?
Is there any convention for this?
