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• Data Structure / Hash Function to link Sets of Ints to Value

  - by Gaminic

  Given n integer id's, I wish to link all possible sets of up to k id's to a constant value. What I'm looking for is a way to translate sets (e.g. {1, 5}, {1, 3, 5} and {1, 2, 3, 4, 5, 6, 7}) to unique values. Guarantees: n < 100 and k < 10 (again: set sizes will range in [1, k]). The order of id's doesn't matter: {1, 5} == {5, 1}. All combinations are possible, but some may be excluded. All sets and values are constant and made only once. No deletes or inserts, no value updates. Once generated, the only operations taking place will be look-ups. Look-ups will be frequent and one-directional (given set, look up value). There is no need to sort (or otherwise organize) the values. Additionally, it would be nice (but not obligatory) if "neighboring" sets (drop one id, add one id, swap one id, etc) are easy to reach, as well as "all sets that include at least this set". Any ideas?

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• MySQL: optimization of table (indexing, foreign key) with no primary keys

  - by Haradzieniec

  Each member has 0 or more orders. Each order contains at least 1 item. memberid - varchar, not integer - that's OK (please do not mention that's not very good, I can't change it). So, thera 3 tables: members, orders and order_items. Orders and order_items are below: CREATE TABLE `orders` ( `orderid` INT(11) UNSIGNED NOT NULL AUTO_INCREMENT, `memberid` VARCHAR( 20 ), `Time` TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP , `info` VARCHAR( 3200 ) NULL , PRIMARY KEY (orderid) , FOREIGN KEY (memberid) REFERENCES members(memberid) ) ENGINE = InnoDB; CREATE TABLE `order_items` ( `orderid` INT(11) UNSIGNED NOT NULL, `item_number_in_cart` tinyint(1) NOT NULL , --- 5 items in cart= 5 rows `price` DECIMAL (6,2) NOT NULL, FOREIGN KEY (orderid) REFERENCES orders(orderid) ) ENGINE = InnoDB; So, order_items table looks like: orderid - item_number_in_cart - price: ... 1000456 - 1 - 24.99 1000456 - 2 - 39.99 1000456 - 3 - 4.99 1000456 - 4 - 17.97 1000457 - 1 - 20.00 1000458 - 1 - 99.99 1000459 - 1 - 2.99 1000459 - 2 - 69.99 1000460 - 1 - 4.99 ... As you see, order_items table has no primary keys (and I think there is no sense to create an auto_increment id for this table, because once we want to extract data, we always extract it as WHERE orderid='1000456' order by item_number_in_card asc - the whole block, id woudn't be helpful in queries). Once data is inserted into order_items, it's not UPDATEd, just SELECTed. The questions are: I think it's a good idea to put index on item_number_in_cart. Could anybody please confirm that? Is there anything else I have to do with order_items to increase the performance, or that looks pretty good? I could miss something because I'm a newbie. Thank you in advance.

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• Reading and writing to files simultaneously?

  - by vipersnake005

  Moved the question here. Suppose, I want to store 1,000,000,000 integers and cannot use my memory. I would use a file(which can easily handle so much data ). How can I let it read and write and the same time. Using fstream file("file.txt', ios::out | ios::in ); doesn't create a file, in the first place. But supposing the file exists, I am unable to use to do reading and writing simultaneously. WHat I mean is this : Let the contents of the file be 111111 Then if I run : - #include <fstream> #include <iostream> using namespace std; int main() { fstream file("file.txt",ios:in|ios::out); char x; while( file>>x) { file<<'0'; } return 0; } Shouldn't the file's contents now be 101010 ? Read one character and then overwrite the next one with 0 ? Or incase the entire contents were read at once into some buffer, should there not be atleast one 0 in the file ? 1111110 ? But the contents remain unaltered. Please explain. Thank you.

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• Question on passing a pointer to a structure in C to a function?

  - by worlds-apart89

  Below, I wrote a primitive singly linked list in C. Function "addEditNode" MUST receive a pointer by value, which, I am guessing, means we can edit the data of the pointer but can not point it to something else. If I allocate memory using malloc in "addEditNode", when the function returns, can I see the contents of first-next ? Second question is do I have to free first-next or is it only first that I should free? I am running into segmentation faults on Linux. #include <stdio.h> #include <stdlib.h> typedef struct list_node list_node_t; struct list_node { int value; list_node_t *next; }; void addEditNode(list_node_t *node) { node->value = 10; node->next = (list_node_t*) malloc(sizeof(list_node_t)); node->next->value = 1; node->next->next = NULL; } int main() { list_node_t *first = (list_node_t*) malloc(sizeof(list_node_t)); first->value = 1; first->next = NULL; addEditNode(first); free(first); return 0; }

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• VB looping complication

  - by user1819469

  I have to come up with a program that shifts names in a text box a random amount of times. I have gotten everything up to the point where the names shifts a random amount of times. It only shifts its once, but my messagebox appears through the code as many times as the names should be shifting once i click ok. Does anyone know why the loop is not working for the name shifts. I was thinking maybe the messagebox needs to control the loop, but I have searched endlessly and cannot find how that would be done. Any suggestions or referrals to other sites would be nice thanks. My code is below. Public Class Form1 Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click Dim RandomNumber As Integer Dim min, max As Integer Dim temp, temp2, temp3, temp4, temp5, temp6 As String Dim i As Integer min = 3 max = 11 Randomize() RandomNumber = Int((max - min + 1) * Rnd() + min) temp = n1.Text temp2 = n2.Text temp3 = n3.Text temp4 = n4.Text temp5 = n5.Text temp6 = n6.Text For i = 0 To RandomNumber - 1 n1.Text = temp6 n2.Text = temp n3.Text = temp2 n4.Text = temp3 n5.Text = temp4 n6.Text = temp5 MessageBox.Show("Shift " & i & " of " & RandomNumber & " complete") Next End Sub End Class

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• Can the size of a structure change after compiled?

  - by Sarah Altiva

  Hi, suppose you have the following structure: #include <windows.h> // BOOL is here. #include <stdio.h> typedef struct { BOOL someBool; char someCharArray[100]; int someIntValue; BOOL moreBools, anotherOne, yetAgain; char someOthercharArray[23]; int otherInt; } Test; int main(void) { printf("Structure size: %d, BOOL size: %d.\n", sizeof(Test), sizeof(BOOL)); } When I compile this piece of code in my machine (32-bit OS) the output is the following: Structure size: 148, BOOL size: 4. I would like to know if, once compiled, these values may change depending on the machine which runs the program. E.g.: if I ran this program in a 64-bit machine, would the output be the same? Or once it's compiled it'll always be the same? Thank you very much, and forgive me if the answer to this question is obvious...

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• Creating Thread in Win32

  - by Dave18

  Does ThreadFunc() gets called two times here? sometimes I notice a single call and sometimes none at all. #include <windows.h> #include <stdio.h> DWORD WINAPI ThreadFunc(LPVOID); int main() { HANDLE hThread; DWORD threadld; hThread = CreateThread(NULL, 0, ThreadFunc, 0, 0, &threadld ); printf("Thread is running\n"); } DWORD WINAPI ThreadFunc(LPVOID p) { printf("In ThreadFunc\n"); return 0; } Output 1 Thread is running In ThreadFunc In ThreadFunc Press any key to continue . . . Output 2 Thread is running In ThreadFunc Press any key to continue . . . Output 3 Thread is running Press any key to continue . . .

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• jQuery slider to load content one at a time

  - by Barrett

  I have a slider that load all of my content at once. Into a div. Like so: external page.php $get_users = mysql_query("SELECT * FROM user WHERE id!='$user_id'"); while ($rows = mysql_fetch_assoc($get_users)) { $id = $rows['id']; $firstname = $rows['firstname']; $display_info .= ' <div class="f_outer" id="' . $id . '"> <div class="f_name likeu">' . $firstname . '</div> </div>'; } echo $display_info; I call this page from my find.php page using bxslider Here is my find.php page below. <script type="text/javascript"> $(function() { var slider = $("#slider1").bxSlider(); $("#slider-like").live('click', function() { slider.goToNextSlide(); return false; }); }); </script> <div id="slider-like>Yes</div> <div id="slider1"> <?PHP include ("external.php"); ?> </div> So what I get is all of my .f_outer div on the find.php page. I have hundreds of user and they will all be loaded at once. I would like to only load one slide at a time. So when I click #slider-like it load one of my dive from my external page.

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• Android designing an app to keep me logged into a wifi access point

  - by MrGibbage

  At the gym where I work out, they have an open wifi access point. The way it is set up, once you "connect", you have to navigate to a web page (it is a 1.1.X.X ip address) and click the "I agree" button, after presumably reading the user agreement. The problem is, they have it set up to log you out once an hour, which always happens in the middle of my workout. I have the SSID remembered, so it connects automatically when I come in range, but I get an android notification that further action is needed to fully connect. What I was wondering is if there a work around so that I don't have to click-through every hour? I was thinking of writing an app that could detect when I was in range, or when "half-connected", and then have it somehow complete the registration process. Perhaps this will have to be done by loading the web page in memory and then somehow clicking the "I agree" button. What I would like help with is: 1) what is the terminology involved here? What state is the connection in when I am connected, but I haven't clicked through? What other connection states may apply? If I knew that, I might just be able to research this and come up with a solution. Are these different states "detectable"? It seems like it is since I get a notification that I need to complete the registration process when I am "half-connected". 2) I know there are plugins for desktop browsers that can click buttons (like the keepass plugins, which will log you into a site). How could I replicate this in Android? Ideally I would like to do it internally, in memory, rather than firing up a browser. Possible? Comments? Is my understanding and thought process sound here, or am I overlooking something?

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• I want to add and remove items from a menu with PHP.

  - by CDeanMartin

  This menu will need to be updated daily. <html><head></head><body> <h1> Welcome to Burgerama </h1> <?php include("menuBuilder.php"); showBurgerMenu(); ?> </body></html> Menu items are stored in the database. Items have a display field; if it is on, the item should be displayed on the menu. The menu only displays 4 or 5 "specials" at a time, and the manager needs to change menu items easily. I want to make a menu editing page like this: <?php include("burger_queries.php"); dbconnect("burger_database"); foreach($menuItem in burger_database) { echo createToggleButton($menuItem); } ?> .. with a toggle button for each menu item. Ideally the button will be labeled with the menu item, in blue if the item is "on", and red if the item is "off." Clicking the button switches between "on" and "off" I am stuck trying to a get a button to execute an UPDATE query on its corresponding menu item.

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• Importing a C DLL's functions into a C++ program

  - by bobobobo

  I have a 3rd party library that's written in C. It exports all of its functions to a DLL. I have the .h file, and I'm trying to load the DLL from my C++ program. The first thing I tried was surrounding the parts where I #include the 3rd party lib in #ifdef __cplusplus extern "C" { #endif and, at the end #ifdef __cplusplus } // extern "C" #endif But the problem there was, all of the DLL file function linkage looked like this in their header files: a_function = (void *)GetProcAddress(dll, "a_function"); While really a_function had type int (*a_function) (int *). Apparently MSVC++ compiler doesn't like this, while MSVC compiler does not seem to mind. So I went through (brutal torture) and fixed them all to the pattern typedef int (*_a_function) (int *); _a_function a_function ; Then, to link it to the DLL code, in main(): a_function = (_a_function)GetProcAddress(dll, "a_function"); This SEEMS to make the compiler MUCH, MUCH happier, but it STILL complains with this final set of 143 errors, each saying for each of the DLL link attempts: error LNK2005: _a_function already defined in main.obj main.obj Multiple symbol definition errors.. sounds like a job for extern! SO I went and made ALL the function pointer declarations as follows: function_pointers.h typedef int (*_a_function) (int *); extern _a_function a_function ; And in a cpp file: function_pointers.cpp #include "function_pointers.h" _a_function a_function ; ALL fine and dandy.. except for linker errors now of the form: error LNK2001: unresolved external symbol _a_function main.obj Main.cpp includes "function_pointers.h", so it should know where to find each of the functions.. I am bamboozled. Does any one have any pointers to get me functional? (Pardon the pun..)

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• page loads twice due to js code

  - by Cristian Boariu

  Hi, I have this div inside a repeater, where i set the class, onmouseover and onmouseout properties from code behind: <div id="Div1" runat="server" class="<%# getClassProduct(Container.ItemIndex) %>" onmouseover="<%# getClassProductOver(Container.ItemIndex) %>" onmouseout="<%# getClassProductOut(Container.ItemIndex) %>"> codebehind: public String getClassProduct(Object index) { int indexItem = Int32.Parse(index.ToString()); if (indexItem == 3) return "produs_box produs_box_wrap overitem lastbox"; else return "produs_box produs_box_wrap overitem"; } public String getClassProductOver(Object index) { int indexItem = Int32.Parse(index.ToString()); if (indexItem == 3) return "this.className='produs_box produs_box_wrap overitem_ lastbox'"; else return "this.className='produs_box produs_box_wrap overitem_'"; } public String getClassProductOut(Object index) { int indexItem = Int32.Parse(index.ToString()); if (indexItem == 3) return "this.className='produs_box produs_box_wrap overitem lastbox'"; else return "this.className='produs_box produs_box_wrap overitem'"; } Well, the problem is that, my Page_Load is fired twice, and there i have some code which i want to execute only ONCE: if (!Page.IsPostBack) { ..code to execute once } This code is fired initially, and after the page is rendered, it is called again, and executed again due to that js... Anyone can recommend a workaround? Thanks in advance.

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• Can somebody please explain this recursive function for me?

  - by capncoolio

  #include <stdio.h> #include <stdlib.h> void reprint(char *a[]) { if(*a) { printf("%d ",a); reprint(a+1); printf("%s ",*a); } } int main() { char *coll[] = {"C", "Objective", "like", "don't", "I", NULL}; reprint(coll); printf("\n"); return EXIT_SUCCESS; } As the more experienced will know, this prints the array in reverse. I don't quite understand how! I need help understanding what reprint(char *a[]) does. I understand pointer arithmetic to a degree, but from inserting printf's here and there, I've determined that the function increments up to the array end, and then back down to the start, only printing on the way down. However, I do not understand how it does this; all I've managed to understand by looking at the actual code is that if *a isn't NULL, then call reprint again, at the next index. Thanks guys!

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• How to determine number of function arguments dynamically

  - by Kam

  I have the following code: #include <iostream> #include <functional> class test { public: typedef std::function<bool(int)> Handler; void handler(Handler h){h(5);} }; class test2 { public: template< typename Ret2, typename Ret, typename Class, typename Param> inline Ret2 MemFn(Ret (Class::*f)(Param), int arg_num) { if (arg_num == 1) return std::bind(f, this, std::placeholders::_1); } bool f(int x){ std::cout << x << std::endl; return true;} }; int main() { test t; test2 t2; t.handler(t2.MemFn<test::Handler>(&test2::f, 1)); return 0; } It works as expected. I would like to be able to call this: t.handler(t2.MemFn<test::Handler>(&test2::f)); instead of t.handler(t2.MemFn<test::Handler>(&test2::f, 1)); Basically I need MemFn to determine in runtime what Handler expects as the number of arguments. Is that even possible?

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• highlight page selected in pagination?

  - by Mahmoud

  Hey There i have a php page, that shows all products that are stored on the database, so everything in fine, but my problem is that i am trying to highlight or give a color when a selected number is clicked, example, let say i all my product are showing and there are 2 pages, so when the user clicks on next the next fade and number 2 is colored yellow this well help the user to on which page he is below is my php code <?php echo"<a style:'color:#FFF;font-style:normal;'> "; include "im/config.php"; include('im/ps_pagination.php'); $result = ("Select * from product "); $pager = new PS_Pagination($conn, $result, 5, 6, "product=product"); $rs = $pager->paginate(); echo"<div id='image_container'>"; echo $pager->renderFullNav(); echo "<br /><br />\n"; while($row = mysql_fetch_array($rs)){ echo" <div class='virtualpage hidepiece'><a href='gal/".$row['pro_image']."' rel='lightbox[roadtrip]' title='".$row['pro_name']." : ".$row['pro_mini_des']."' style='color:#000'><img src='thumb/".$row['pro_thumb']."' /> </a></div>"; } echo"</div>"; echo "<br /><br />\n"; echo $pager->renderFullNav(); echo"</a>"; ?> Thank everyone

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• log activity. intrusion detection. user event notification ( interraction ). messaging

  - by Julian Davchev

  Have three questions that I somehow find related so I put them in same place. Currently building relatively large LAMP system - making use of messaging(activeMQ) , memcache and other goodies. I wonder if there are best practices or nice tips and tricks on howto implement those. System is user aware - meaning all actions done can be bind to particular logged user. 1. How to log all actions/activities of users? So that stats/graphics might be extracted later for analysing. At best that will include all url calls, post data etc etc. Meaning tons of inserts. I am thinking sending messages to activeMQ and later cron dumping in DB and cron analysing might be good idea here. Since using Zend Framework I guess I may use some request plugin so I don't have to make the log() call all over the code. 2.How to log stuff so may be used for intrusion detection? I know most things might be done on http level using apache mods for example but there are also specific cases like (5 failed login attempts in a row (leads to captcha) etc etc..) This also would include tons of inserts. Here I guess direct usage of memcache might be best approach as data don't seem vital to be permanantly persisted. Not sure if cannot use data from point 1. 3.System will notify users of some events. Like need approval , something broke..whatever.Some events will need feedback(action) from user, others are just informational. Wonder if there is common solutions for needs like this. Example: Based on occuring event(s) user will be notifed (user inbox for example) what happend. There will be link or something to lead him to details of thingy that happend and take action accordingly. Those seem trivial at first look but problem I see if coding it directly is becoming really fast hard to maintain.

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• parsing ssid with iwconfig in c

  - by user1781595

  I am about building a bar for DWM (ubuntu linux), showing wifi details such as the ssid. Thats my code: #include <stdio.h> #include <stdlib.h> int main( int argc, char *argv[] ) { FILE *fp; int status; char path[1035]; /* Open the command for reading. */ fp = popen("iwconfig", "r"); if (fp == NULL) { printf("Failed to run command\n" ); exit; } char s[500]; /* Read the output a line at a time - output it. */ while (fgets(path, sizeof(path)-1, fp) != NULL) { sprintf(s,"%s%s",s, path); } //printf("%s",s); /* close */ pclose(fp); char delimiter[1] = "s"; char *ptr; ptr = strtok(s, delimiter); printf("SSID: %s\n", ptr); return 0; } i am getting overflowerrors and dont know what to do. I dont think, thats a good way to get the ssid either... :/ Suggestions?

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• What new Unicode functions are there in C++0x?

  - by luiscubal

  It has been mentioned in several sources that C++0x will include better language-level support for Unicode(including types and literals). If the language is going to add these new features, it's only natural to assume that the standard library will as well. However, I am currently unable to find any references to the new standard library. I expected to find out the answer for these answers: Does the new library provide standard methods to convert UTF-8 to UTF-16, etc.? Does the new library allowing writing UTF-8 to files, to the console (or from files, from the console). If so, can we use cout or will we need something else? Does the new library include "basic" functionality such as: discovering the byte count and length of a UTF-8 string, converting to upper-case/lower-case(does this consider the influence of locales?) Finally, are any of these functions are available in any popular compilers such as GCC or Visual Studio? I have tried to look for information, but I can't seem to find anything? I am actually starting to think that maybe these things aren't even decided yet(I am aware that C++0x is a work in progress).

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• Do I need to echo html inside included php file

  - by UmeRonaldo

  I just learned how to include php .Here's the index or main php file <!DOCTYPE HTML> <html> <head> </head> <body> <?php include 'header.php'; ?> </body> </html> now in header.php file which way is better to print html Way 1 directly use html without php <header> <h1>Header</h1> </header> Way 2 Using php and echo <?php echo ' <header> <h1>Header</h1> </header> ' ?> Another quick question. Will it work if I use .html for the base or index file ?? sorry for my bad english

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• 3x3 array = 10 numbers

  - by user1708505

  i have this code #include <math.h> #include <stdio.h> const int n = 3; const int s = 3; int getm(int mat[n][s]); int printm(int mat[n][s]); int main() { int m[n][s]; getm(m); printm(m); return 0; } int getm(int mat[n][s]) { for(int x = 0;x < n;x++) { for (int y = 0;y<s;y++) { scanf("%i ", &mat[x][y]); } } return 0; } int printm(int mat[n][s]) { for(int x = 0;x<n;x++) { for(int y = 0;y<s;y++) { printf("%i ", mat[x][y]); if(y==(s-1)) { printf("\n"); } } } } which shoud ask for 9 numbers to make a 3x3 matrix array, but it actually asks for 10 numbers, printm is working well - printing only 9 numbers. Where is error?

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• Why does Go not seem to recognize size_t in a C header file?

  - by Graeme Perrow

  I am trying to write a go library that will act as a front-end for a C library. If one of my C structures contains a size_t, I get compilation errors. AFAIK size_t is a built-in C type, so why wouldn't go recognize it? My header file looks like: typedef struct mystruct { char * buffer; size_t buffer_size; size_t * length; } mystruct; and the errors I'm getting are: gcc failed: In file included from <stdin>:5: mydll.h:4: error: expected specifier-qualifier-list before 'size_t' on input: typedef struct { char *p; int n; } _GoString_; _GoString_ GoString(char *p); char *CString(_GoString_); #include "mydll.h" I've even tried adding either of // typedef unsigned long size_t or // #define size_t unsigned long in the .go file before the // #include, and then I get "gcc produced no output". I have seen these questions, and looked over the example with no success.

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• I can't get that `bus error` to stop sucking.

  - by Koning Baard XIV

  I have this a class called PPString: PPString.h #ifndef __CPP_PPString #define __CPP_PPString #include "PPObject.h" class PPString : public PPObject { char *stringValue[]; public: char *pointerToCharString(); void setCharString(char *charString[]); void setCharString(const char charString[]); }; #endif PPString.cpp #include "PPString.h" char *PPString::pointerToCharString() { return *stringValue; } void PPString::setCharString(char *charString[]) { *stringValue = *charString; } void PPString::setCharString(const char charString[]) { *stringValue = (char *)charString; } I'm trying to set the stringValue using std::cin: main.cpp PPString myString; myString.setCharString("LOLZ"); std::cout << myString.pointerToCharString() << std::endl; char *aa[1000]; std::cin >> *aa; myString.setCharString(aa); std::cout << myString.pointerToCharString() << std::endl; The first one, which uses a const char works, but the second one, with a char doesn't, and I get this output: copy and paste from STDOUT LOLZ im entering a string now... Bus error where the second line is what I entered, followed by pressing the return key. Can anyone help me fixing this? Thanks...

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• android use local service to refresh map UI

  - by urobo

  I don't need a strict code related answer I just need somebody to tell me what I am missing. My application has to retrieve from a web service (xmlrpc) the positions of some users I know and update their position on a MapView. So I decided to use a Service and an Activity extending MapActivity to show results. I thought about two solutions: I ) start the service and make it ask every minute for these positions and send them to the activity as a bundle via intent. (This didn't work out well, since once shown I couldn't find a method to let the activity continue refresh itself until she stop receiving intents+data from the service) II ) Incorporate a thread within the activity which starts the service via context.startService(...) every minute. And the MapUI refresh itself once the service send back an intent and stop itself. (Maybe I will fall in the same problem category as before I haven't tryied yet). I am also giving directions (via maps.google ws) in this way I'd like to refresh only users positions on the map and save the route. What Am I missing do you have any suggestions? related to activities/services internal mechanics, don't know launch modes, use broadcast receivers or intent filters? Thanks in advance

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• How to avoid notice in php when one of the conditions is not true

  - by user225269

  I've notice that when one of the two conditions in a php if statement is not true. You get an undefined index notice for the statement that is not true. And the result in my case is a distorted web page. For example, this code: <?php session_start(); if (!isset($_SESSION['loginAdmin']) && ($_SESSION['loginAdmin'] != '')) { header ("Location: loginam.php"); } else { include('head2.php'); } if (!isset($_SESSION['login']) && ($_SESSION['login'] != '')) { header ("Location: login.php"); } else { include('head3.php'); } ?> If one of the if statements is not true. The one that is not true will give you a notice that it is undefined. In my case it says that the session 'login' is not defined. If session 'LoginAdmin' is used. What can you recommend that I would do in order to avoid these undefined index notice.

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• How do I daemonize an arbitrary script in unix?

  - by dreeves

  I'd like a daemonizer that can turn an arbitrary, generic script or command into a daemon. There are two common cases I'd like to deal with: I have a script that should run forever. If it ever dies (or on reboot), restart it. Don't let there ever be two copies running at once (detect if a copy is already running and don't launch it in that case). I have a simple script or command line command that I'd like to keep executing repeatedly forever (with a short pause between runs). Again, don't allow two copies of the script to ever be running at once. Of course it's trivial to write a "while(true)" loop around the script in case 2 and then apply a solution for case 1, but a more general solution will just solve case 2 directly since that applies to the script in case 1 as well (you may just want a shorter or no pause if the script is not intended to ever die (of course if the script really does never die then the pause doesn't actually matter)). Note that the solution should not involve, say, adding file-locking code or PID recording to the existing scripts. More specifically, I'd like a program "daemonize" that I can run like % daemonize myscript arg1 arg2 or, for example, % daemonize 'echo `date` >> /tmp/times.txt' which would keep a growing list of dates appended to times.txt. (Note that if the argument(s) to daemonize is a script that runs forever as in case 1 above, then daemonize will still do the right thing, restarting it when necessary.) I could then put a command like above in my .login and/or cron it hourly or minutely (depending on how worried I was about it dying unexpectedly). NB: The daemonize script will need to remember the command string it is daemonizing so that if the same command string is daemonized again it does not launch a second copy. Also, the solution should ideally work on both OS X and linux but solutions for one or the other are welcome. (If I'm thinking of this all wrong or there are quick-and-dirty partial solutions, I'd love to hear that too.)

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