file-handling

I'm using: file_put_contents("peopleList.txt", $person, FILE_APPEND | LOCK_EX); to write to the end of a file and to make sure no one else (or script) is also writing to the same file at the same time. The PHP manual says it will return a falsy value if unsuccessful. If it cannot obtain a lock on the file, will it fail or keep trying until it can? If it does fail when no lock can be obtained, what would be the best way to go about ensuring the data is written? Perhaps looping the function in a while loop until it does not return false (cringe) or simply providing the user (website visiter)

I am working with a framegrabber and need to get the images from computer memory and save them on an image file. after trying for couple of days I end up with the following 2 functions, which creates a file and windows OS is able to run the .bmp file, but the bitmap file is black (the image size is 900KB , 640*480). does any body has any idea why, the picture is in black? here are the two functions : LPSTR CreateBMP( HWND hAppWnd, int nImageType ) { void * pWinGBits = NULL; int i; Z_BITMAPINFO zWinGHeader; // bitmapinfo for cerating the DIB // create DC for bitmap. hDCBits = CreateCompatibleDC

I have data in the following format in a text file. Filename - empdata.txt Note that there are no blank space between the lines. Sl|EmployeeID|Name|Department|Band|Location 1|327427|Brock Mcneil|Research and Development|U2|Pune 2|310456|Acton Golden|Advertising|P3|Hyderabad 3|305540|Hollee Camacho|Payroll|U3|Bangalore 4|218801|Simone Myers|Public Relations|U3|Pune 5|144051|Eaton Benson|Advertising|P1|Chennai I have a class like this class empdata { public: int sl,empNO; char name[20],department[20],band[3],location[20]; }; I created an array of objects of class empdata. How to read the data

I was reading some project code and I found this,here MembersOfLibrary() is a constructor of class MenberOfLibrary class MembersOfLibrary { public: MembersOfLibrary(); ~MembersOfLibrary() {} void addMember(); void removeMember(); unsigned int searchMember(unsigned int MembershipNo); void searchMember(unsigned char * name); void displayMember(); private: Members libMembers; }; MembersOfLibrary::MembersOfLibrary() { fstream memberData; memberData.open("member.txt", ios::in|ios::out); if(!memberData) { cout<<"\nNot able to create a file. MAJOR OS ERROR!! \n"; } memberData.close(); } I m not able

Is it possible to use exceptions with file opening as an alternative to using .is_open() ? For example: ifstream input; try{ input.open("somefile.txt"); }catch(someException){ //Catch exception here } If so, what type is someException ? http://en.cppreference.com/w/cpp/io/basic_ios/exceptions Also read this answer 11085151 which references this article // ios::exceptions #include <iostream> #include <fstream> using namespace std; void do_something_with(char ch) {} // Process the character int main () { ifstream file; file.exceptions ( ifstream::badbit ); // No need to check failbit try { file