EndOfFile in C - EOF
What do you put in to end the program, -1, doesn't work: #include <stdio.h> //copy input to output main() { char c; c = getchar(); while(c != EOF) { putchar(c); c = getchar(); } } ...
c
[sqlite/C++] Saving to disk an in-memory database
I made a database through sqlite in c++. The db has been created in memory (using the ":memory:" parameter insted of a filename), in order to have a very quick behavior. The database is created by the following lines: sqlite3* mem_database; if((SQLITE_OK == sqlite3_open(":memory:", &mem_database)){ // The db has been correctly cr...
How to implement a timer in C on windows
Hello All, How do I create a timer in C and after the time expires ,I should be able to call a callback function . The platform is windows. Can someone guide me Regards, Mithun ...
cannot find -lsocket, compiling problem in client-server program?
I am trying to do some socket programming, writing a simple client-server program. But when I try to compile the program, I get this error. gcc -o showip showip.c -lnsl -lsocket -lresolv showip.cc: In function ‘int main(int, char**)’: /usr/bin/ld.real: cannot find -lsocket collect2: ld returned 1 exit status I try to install lib doing...
testing code in C C++
Hi I don't know how you guys test your code every time you code a little and for different levels of testing: unit testing, Integration testing, ... For example, for unit testing a function you just wrote, do you write another whole set of main function and Makefile to test it? Or do you modify the main function of your project to test...
double free problem
How to solve a double free problem by writing a wrapper function with name free so that i need not change every free call in my source code? ...
What are the differences between if, else, and else if?
I am trying to discern the difference between if else else if When do you use them and when not? I have a homework assignment with a ton of instances and I am running into code error due to not knowing the differences between each. Can someone please define how to use these? ...
What is the correct way to handle "out of memory"?
Recently, I work on a video player program on Windows for a CCTV program. As the program has to decode and play many videos streams at the same time, I think it might meet the situation that malloc will fail and I add checking after every malloc. But genrally speaking, in these code of open source programs that I've read in open sourc...
How to do Variable Substitution with Flex/Lex and Yacc/Bison
Wikipedia's Interpolation Definition I am just learning flex / bison and I am writing my own shell with it. I am trying to figure out a good way to do variable interpolation. My initial approach to this was to have flex scan for something like ~ for my home directory, or $myVar , and then set what the yyval.stringto what is returned u...
windows process management
Why does the root directory of a process, started by a windows process manager, change to the directory of where the pm is located? Using msdn process manager code to create a pm service to run a few exes. The exes save log files in the root relative to their location. When started by the process manager, they are saving to the process...
How can malloc() cause a SIGSEGV?
I have an odd bug in my program, it appears to me that malloc() is causing a SIGSEGV, which as far as my understanding goes does not make any sense. I am using a library called simclist for dynamic lists. Here is a struct that is referenced later: typedef struct { int msgid; int status; void* udata; list_t queue; } msg_...
Need better way to format a phone number in C.
I have a character array that contains a phone number of the form: "(xxx)xxx-xxxx xxxx" and need to convert it to something of the form: "xxx-xxx-xxxx" where I would just truncate the extension. My initial pass at the function looks like this: static void formatPhoneNum( char *phoneNum ) { unsigned int i; int numNumbers = 0; ...
directory structures C++
C:\Projects\Logs\RTC\MNH\Debug C:\Projects\Logs\FF Is there an expression/string that would say go back until you find "Logs" and open it? (assuming you were always below it) The same executable is run out of "Debug", "MNH" or "FF" at different times, the executable always should save it's log files into "Logs". What expression wou...
how to get date and time value in C program
I have something like this char *current_day, *current_time; system("date +%F); system("date +%T); It prints the current day and time in the stdout, but I want to get this output or assign them in current_day and current_time variables, so that I can do some processing with those values later on. current_day ==> current day current_t...
Full-featured date and time library
I'm wondering if anyone knows of a good date and time library that has correctly-implemented features like the following: Microsecond resolution Daylight savings Example: it knows that 2:30am did not exist in the US on 8 March 2009 for timezones that respect daylight savings. I should be able to specify a timezone like "US/Eastern" a...
Access Gmail in C
Is there an equivalent for the python libgmail in “C”? Edit: I am trying to achieve the equivalent of GmailFS in C. Appreciate if you can point me to an open source library. This is for a hobby project. ...
fclose() causing segmentation fault
I have a tab-delimited text file that I am parsing. Its first column contains strings of the format chrX, where X denotes a set of strings, e.g., "1", "2", ..., "X", "Y". These are each stored in a char* called chromosome, as the file is parsed. The text file is sorted on the first column lexicographically, i.e., I will have a number...
About atomicity guarantee in C
On x86 machines, instructions like inc, addl are not atomic and under SMP environment it is not safe to use them without lock prefix. But under UP environment it is safe since inc, addl and other simple instructions won't be interrupted. My problem is that, given a C-level statement like x = x + 1; Is there any guarantees that C com...
Running C code directly in the browser?
Performance considerations aside, is there any known way to take existing C, C++, or Objective C code and run it directly in the browser? For example, a compiler that converts all the code into some interpreted language that can be run in the browser. Like Javascript, or Actionscript and the Flash player, or I suppose Java and the JVM. ...
Which library to use for C data structures with GCC
Hello all, I'm about to start a new project in C. I'm currently investigating a library for C data structures. I've found plenty of them. But which one would you recommend? I'm currently considering to use gdsl or glib . The important properties of a library for me is: Robustness and reliability of the code. Documentation. Readabilit...