Search Results

Search found 19376 results on 776 pages for 'char array'.

Page 274/776 | < Previous Page | 270 271 272 273 274 275 276 277 278 279 280 281  | Next Page >

  • Reading a file with a supplied name in C++

    - by Cosmina
    I must read a file with a given name (it's caled "hamlet.txt"). The class used to read the file is defined like this #ifndef READWORDS_H #define READWORDS_H /** * ReadWords class. Provides mechanisms to read a text file, and return * capitalized words from that file. */ using namespace std; #include <string> #include <fstream> class ReadWords { public: /** * Constructor. Opens the file with the default name "text.txt". * Program exits with an error message if the file does not exist. */ ReadWords(); /** * Constructor. Opens the file with the given filename. * Program exits with an error message if the file does not exist. * @param filename - a C string naming the file to read. */ ReadWords(char *filename); My definition of the members of the classis this: #include<string> #include<fstream> #include<iostream> #include "ReadWords.h" using namespace std; ReadWords::ReadWords() { wordfile.open("text.txt"); if( !wordfile ) { cout<<"Errors while opening the file!"<<endl; } } ReadWords::ReadWords(char *filename) { wordfile.open(filename); if ( !wordfile ) { cout<<"Errors while opening the file!"<<endl; } wordfile>>nextword; } And the main to test it. using namespace std; #include #include #include "ReadWords.h" int main() { char name[30]; cout<<"Please input a name for the file that you wish to open"; cin>>name; ReadWords x( name[] ); } When I complie it gives me the error: main.cpp:14: error: expected primary-expression before ']' token I know it's got something to do with the function ReadWords( char *filename), but I do not know what. Any help please?

    Read the article

  • How to get values after dictionary sorting by values with linq

    - by user301639
    hey, I've a dictionary, which i sorted by value with linq, how can i get those sorted value from the sorted result i get that's what i did so far Dictionary<char, int> lettersAcurr = new Dictionary<char, int>();//sort by int value var sortedDict = (from entry in lettersAcurr orderby entry.Value descending select entry); during the debug i can see that sortedDic has a KeyValuePar, but i cant accesses to it thanks for help

    Read the article

  • how to get ip address of my computer

    - by asthagoyal
    hello i want to get ipaddress of my computer in variable ip thru this code but it assign nothing in ip char comm[100]; int s=0; char ip[100]; sprintf(comm,"export ip=`/sbin/ifconfig eth0 | grep 'inet addr:' | cut -d: -f2 | awk '{ print $1}'`"); s=system(comm); printf("\n ip is %s",ip);

    Read the article

  • pthread and recursively calling execvp in C

    - by eduke
    To begin I'm sorry for my english :) I looking for a way to create a thread each time my program finds a directory, in order to call the program itself but with a new argv[2] argument (which is the current dir). I did it successfully with fork() but with pthread I've some difficulties. I don't know if I can do something like that : #include <unistd.h> #include <stdlib.h> #include <stdio.h> #include <string.h> #include <sys/types.h> #include <sys/stat.h> #include <sys/wait.h> #include <dirent.h> int main(int argc, char **argv) { pthread_t threadID[10] = {0}; DIR * dir; struct dirent * entry; struct stat status; pthread_attr_t attr; pthread_attr_init(&attr); int i = 0; char *res; char *tmp; char *file; if(argc != 3) { printf("Usage : %s <file> <dir>\n", argv[0]); exit(EXIT_FAILURE); } if(stat(argv[2],&status) == 0) { dir = opendir(argv[2]); file = argv[1]; } else exit(EXIT_FAILURE); while ((entry = readdir(dir))) { if (strcmp(entry->d_name, ".") && strcmp(entry->d_name, "..")) { tmp = malloc(strlen(argv[2]) + strlen(entry->d_name) + 2); strcpy(tmp, argv[2]); strcat(tmp, "/"); strcat(tmp, entry->d_name); stat(tmp, &status); if (S_ISDIR(status.st_mode)) { argv[2] = tmp; pthread_create( &threadID[i], &attr, execvp(argv[0], argv), NULL); printf("New thread created : %d", i); i++; } else if (!strcmp(entry->d_name, file)) { printf(" %s was found - Thread number = %d\n",tmp, i); break; } free(tmp); } } pthread_join( threadID[i] , &res ); exit(EXIT_SUCCESS); } Actually it doesn't works : pthread_create( &threadID[i], &attr, execvp(argv[0], argv), NULL); I have no runtime error, but when the file to find is in another directory, the thread is not created and so execvp(argv[0], argv) is not called... Thank you for you help, Simon

    Read the article

  • Unintentional concatenation in Bison/Yacc grammar.

    - by troutwine
    I am experimenting with lex and yacc and have run into a strange issue, but I think it would be best to show you my code before detailing the issue. This is my lexer: %{ #include <stdlib.h> #include <string.h> #include "y.tab.h" void yyerror(char *); %} %% [a-zA-Z]+ { yylval.strV = yytext; return ID; } [0-9]+ { yylval.intV = atoi(yytext); return INTEGER; } [\n] { return *yytext; } [ \t] ; . yyerror("invalid character"); %% int yywrap(void) { return 1; } This is my parser: %{ #include <stdio.h> int yydebug=1; void prompt(); void yyerror(char *); int yylex(void); %} %union { int intV; char *strV; } %token INTEGER ID %% program: program statement EOF { prompt(); } | program EOF { prompt(); } | { prompt(); } ; args: /* empty */ | args ID { printf(":%s ", $<strV>2); } ; statement: ID args { printf("%s", $<strV>1); } | INTEGER { printf("%d", $<intV>1); } ; EOF: '\n' %% void yyerror(char *s) { fprintf(stderr, "%s\n", s); } void prompt() { printf("> "); } int main(void) { yyparse(); return 0; } A very simple language, consisting of no more than strings and integer and a basic REPL. Now, you'll note in the parser that args are output with a leading colon, the intention being that, when combined with the first pattern of the rule of the statement the interaction with the REPL would look something like this: > aaa aa a :aa :a aaa> However, the interaction is this: > aaa aa a :aa :a aaa aa aa > Why does the token ID in the following rule statement: ID args { printf("%s", $<strV>1); } | INTEGER { printf("%d", $<intV>1); } ; have the semantic value of the total input string, newline included? How can my grammar be reworked so that the interaction I intended?

    Read the article

  • strtok problem in calling

    - by Moony
    I have a function using strtok like this void f1(char *name) { ... char *tmp; tmp = strtok(names, " ,"); while(tmp) { ... tmp = strtok(NULL, " ,"); } ... } And i have a call f1("abc,def"); Problem is that in first call f1 gets abc,def and in 2nd call gets just abc I am confused.. Why is this so?

    Read the article

  • Explain why MickroC pic18f4550 HID example works

    - by Dr Deo
    MickroC compiler has a library for HID(Human Interface Device) usb communication. In the supplied samples, they specify that the buffers below should be in USB ram and use a pic18f4550. unsigned char readbuff[64] absolute 0x500; // Buffers should be in USB RAM, please consult datasheet unsigned char writebuff[64] absolute 0x540; But the pic18f4550 datasheet says USB ram ranges from 400h to 4FFh So why does their example work when their buffers appear not to be between 400h to 4FFh? Link to full source

    Read the article

  • Java Operator Precedence Comparison

    - by Andrew
    Does java have a built-in method to compare precedence of two operators? For example, if I have a char '/' and a char '+' is there a method I can call that compares the two and returns true/false if the first is greater than the second (e.g. true)?

    Read the article

  • How do I get the next token in a Cstring if I want to use it as an int? (c++)

    - by Van
    My objective is to take directions from a user and eventually a text file to move a robot. The catch is that I must use Cstrings(such as char word[];) rather than the std::string and tokenize them for use. the code looks like this: void Navigator::manualDrive() { char uinput[1]; char delim[] = " "; char *token; cout << "Enter your directions below: \n"; cin.ignore(); cin.getline (uinput, 256); token=strtok(uinput, delim); if(token == "forward") { int inches; inches=token+1; travel(inches); } } I've never used Cstrings I've never tokenized anything before, and I don't know how to write this. Our T.A.'s expect us to google and find all the answers because they are aware we've never been taught these methods. Everyone in my lab is having much more trouble than usual. I don't know the code to write but I know what I want my program to do. I want it to execute like this: 1) Ask for directions. 2) cin.getline the users input 3) tokenize the inputed string 4) if the first word token == "forward" move to the next token and find out how many inches to move forward then move forward 5) else if the first token == "turn" move to the next token. if the next token == "left" move to the next token and find out how many degrees to turn left I will have to do this for forward x, backward x, turn left x, turn right x, and stop(where x is in inches or degrees). I already wrote functions that tell the robot how to move forward an inch and turn in degrees. I just need to know how to convert the inputted strings to all lowercase letters and move from token to token and convert or extract the numbers from the string to use them as integers. If all is not clear you can read my lab write up at this link: http://www.cs.utk.edu/~cs102/robot_labs/Lab9.html If anything is unclear please let me know, and I will clarify as best I can.

    Read the article

  • Need unicode characters in UITableView from SQLlite database

    - by Lee Armstrong
    I have some NSString varibales that incude items like Ð and Õ and if I do cell.textLabel.text = person.name; and if it contains one of those characters the cell.textlabel is blank! I have discovered that if I use NSString *col1 = [NSString stringWithUTF8String:(char *)sqlite3_column_text(compiledStatement, 0)]; To pull my data back it pulls back null, however using the deprectared method NSString *col1 = [NSString stringWithCString:(char *)sqlite3_column_text(compiledStatement, 0)]; Shows the characters! Any ideas?

    Read the article

  • Struct declaration error in C

    - by Spidfire
    ive got a struct problem it returns: cd.h:15: error: two or more data types in declaration specifiers its probably something simple ... struct cd { char titel[32]; char artiest[32]; int speelduur; }; typedef struct cd CD; struct cdlijst{ CD *item; struct cdlijst *next; } typedef struct cdlijst CDLijst;

    Read the article

  • Reading and writing C++ vector to a file

    - by JB
    For some graphics work I need to read in a large amount of data as quickly as possible and would ideally like to directly read and write the data structures to disk. Basically I have a load of 3d models in various file formats which take too long to load so I want to write them out in their "prepared" format as a cache that will load much faster on subsequent runs of the program. Is it safe to do it like this? My worries are around directly reading into the data of the vector? I've removed error checking, hard coded 4 as the size of the int and so on so that i can give a short working example, I know it's bad code, my question really is if it is safe in c++ to read a whole array of structures directly into a vector like this? I believe it to be so, but c++ has so many traps and undefined behavour when you start going low level and dealing directly with raw memory like this. I realise that number formats and sizes may change across platforms and compilers but this will only even be read and written by the same compiler program to cache data that may be needed on a later run of the same program. #include <fstream> #include <vector> using namespace std; struct Vertex { float x, y, z; }; typedef vector<Vertex> VertexList; int main() { // Create a list for testing VertexList list; Vertex v1 = {1.0f, 2.0f, 3.0f}; list.push_back(v1); Vertex v2 = {2.0f, 100.0f, 3.0f}; list.push_back(v2); Vertex v3 = {3.0f, 200.0f, 3.0f}; list.push_back(v3); Vertex v4 = {4.0f, 300.0f, 3.0f}; list.push_back(v4); // Write out a list to a disk file ofstream os ("data.dat", ios::binary); int size1 = list.size(); os.write((const char*)&size1, 4); os.write((const char*)&list[0], size1 * sizeof(Vertex)); os.close(); // Read it back in VertexList list2; ifstream is("data.dat", ios::binary); int size2; is.read((char*)&size2, 4); list2.resize(size2); // Is it safe to read a whole array of structures directly into the vector? is.read((char*)&list2[0], size2 * sizeof(Vertex)); }

    Read the article

  • Why SQL2008 debugger would NOT step into a certain child stored procedure

    - by John Galt
    I'm encountering differences in T-SQL with SQL2008 (vs. SQL2000) that are leading me to dead-ends. I've verified that the technique of sharing #TEMP tables between a caller which CREATES the #TEMP and the child sProc which references it remain valid in SQL2008 See recent SO question. My core problem remains a critical "child" stored procedure that works fine in SQL2000 but fails in SQL2008 (i.e. a FROM clause in the child sProc is coded as: SELECT * FROM #AREAS A) despite #AREAS being created by the calling parent. Rather than post snippets of the code now, here is another symptom that may help you suggest something. I fired up the new debugger in SQL Mgmt Studio: EXEC dbo.AMS1 @S1='06',@C1='037',@StartDate='01/01/2008',@EndDate='07/31/2008',@Type=1,@ACReq = 1,@Output = 0,@NumofLines = 30,@SourceTable = 'P',@LoanPurposeCatg='P' This is a very large sProc and the key snippet that is weird is the following: **create table #Areas ( State char(2) , County char(3) , ZipCode char(5) NULL , CityName varchar(28) NULL , PData varchar(3) NULL , RData varchar(3) NULL , SMSA_CD varchar(10) NULL , TypeCounty varchar(50) , StateAbbr char(2) ) EXECUTE dbo.AMS_I_GetAreasV5 -- this child populates #Areas @SMSA = @SMSA , @S1 = @S1 , @C1 = @C1 , @Z1 = @Z1 , @SourceTable = @SourceTable , @CustomID = @CustomID , @UserName = @UserName , @CityName = @CityName , @Debug=0 EXECUTE dbo.AMS_I_GetAreas_FixAC -- this child cannot reference #Areas @StartDate = @StartDate , @EndDate = @EndDate , @SMSA_CD = @SMSA_CD , @S1 = @S1 , @C1 = @C1 , @Z1 = @Z1 , @CityName = @CityName , @CustomID = @CustomID , @Debug=0 -- continuation of the parent sProc** I can step through the execution of the parent stored procedure. When I get to the first child sproc above, I can either STEP INTO dbo.AMS_I_GetAreasV5 or STEP OVER its execution. When I arrive at the invocation of the 2nd child sProc - dbo.AMS_I_GetAreas_FixAC - I try to STEP INTO it (because that is where the problem statement is) and STEP INTO is ignored (i.e. treated like STEP OVER instead; yet I KNOW I pressed F11 not F10). It WAS executed however, because when control is returned to the statement after the EXECUTE, I click Continue to finish execution and the results windows shows the errors in the dbo.AMS_I_GetAreas_FixAC (i.e. the 2nd child) stored procedure. Is there a way to "pre-load" an sProc with the goal of setting a breakpoint on its entry so that I can pursue execution inside it? In summary, I wonder if the inability to step into a given child sproc might be related to the same inability of this particular child to reference a #temp created by its parent (caller).

    Read the article

  • Using an ampersand in scanf()

    - by Rob
    When I compile scanf("%s", &var);, gcc sends back a warning: warning: format ‘%s’ expects type ‘char *’, but argument 2 has type ‘char (*)[20]’ however when I compile scanf("%s", var);, no warning is applied. Both pieces of code work and the book I am reading specifically says to use the ampersand, but even it doesn't in some of the examples. My question is, should I continue to use the ampersand, even when the book doesn't specify?

    Read the article

  • Filter string in C

    - by Paul Tarjan
    How can I filter a string in c? I want to remove anything that isn't [a-z0-9_]. int main(int argc, char ** argv) { char* name = argv[1]; // remove anything that isn't [a-z0-9_] printf("%s", name); }

    Read the article

  • C programming doubt!!!

    - by aks
    Hi, I am having a programming doubt? Please have a look at the below mentioned code snippet and tell me the difference? int main() { struct sockaddr_in serv_addr, cli_addr; /* Initialize socket structure */ bzero((char *) &serv_addr, sizeof(serv_addr)); } Now, what if i do something similar without typecasting (char *), then also i feel it will do the same thing? Can someone clarify? /* Initialize socket structure */ bzero( &serv_addr, sizeof(serv_addr));

    Read the article

  • How can I share dynamic data between Applications?

    - by Ehsan
    Hi, I use CreateFileMapping, but this method does not useful,because only static structure can be shared by this method. for example this method is good for following structure: struct MySharedData { unsigned char Flag; int Buff[10]; }; but it's not good for : struct MySharedData { unsigned char Flag; int *Buff; }; would be thankful if somebody guide me on this, Thanks in advance!

    Read the article

  • Variable popen calls in C

    - by Bushman
    I'm trying to execute MS-DOS DEL commands inside a Win32 C program, and I already know that system and popen can be used for this. However, the problem is that both require string literals (type const char) for the commands, and I need something like the DOS equivalent of dir ~ | grep -P '/\d{7,8}\.exe$/' | rm, which obviously can't use string literals. Is there some other subprocess function in C that allows for char arrays as arguments for process names?

    Read the article

  • Problem with pointers

    - by noname
    OK, i have a strange problem. I have this piece of code: int *p; int test; p=&test; In Visual C++ express, in my exsisting project, I get this error: missing type specifier - int assumed. 'p' : 'int' differs in levels of indirection from 'char *' 'initializing' : cannot convert from 'char *' to 'int' But when i create new project, same code is fine. Whats the problem please?

    Read the article

< Previous Page | 270 271 272 273 274 275 276 277 278 279 280 281  | Next Page >