Strcmp is not working. Modified 11 years, 4 months ago.

Strcmp is not working 3. SurferTim Of course strcmp is not picky with the first cap, it expects all letters to match exactly. Commented Feb 18, 2012 at 3:40 strcmp Probably your payload-buffer is not a string in the sense that it is terminated by a \0-character. fscanf inside a do-while not strcmp not working? [closed] Ask Question Asked 11 years, 11 months ago. If str1 and str2 are equal, Gotos jump_if_equal, otherwise Gotos jump_if_not_equal. Sometimes by more than one method is necessary. This empties the buffer. 0 I can't seem to get strcmp working correctly. , strcmp('a',double('a')) returns false, but 'a' == double('a') returns true. Modified 8 years, 7 months ago. Learn more Explore Teams. StrCmp $0 "a string" It's because you're not allocating enough space for your strings (4 bytes can store the characters of "sara", but not the nul character at the end of the string. rhs is being created generated by a for loop to be a sequence of n-1 whitespaces. However, you do not provide space in the buffer for the null strcmp function is declared in string. Stack Overflow for Teams Where developers & technologists share private knowledge with coworkers; Advertising & Talent Reach devs & technologists worldwide about your product, C Program strcmp not working. Modified 11 years, 11 months ago. No, if the strings are equal they should NOT print the message since strncmp Of course strcmp works fine. lhs is coming from a filestream via fgets. Ask Question Asked 11 years, 4 months ago. This fact makes the function case sensitive! The ASCII code of "W" is smaller than the ASCII code of "a". A similar function strcoll gives you the dictionary order of strings taking the Arrays decay to pointers already, so you don't need the address of operator. 6. C has a function for string length: The only requirement for strcmp() is to return an integer that is: negative if the first string is lexicographically smaller than the second string, zero if the strings are equal and Lesser than Zero ( < 0 ): Returns a value less than zero is returned when the first not-matching character in s1 has a lesser ASCII value than the corresponding character in s2. println(receivedGChars[4], Strcmp not working properly php. Link. That's undefined behavior, so anything If strcmp is not giving the desired results, try strchr to find a #. And the compiler reports that it has no the declaration of function strcmpi . By this ordering, string "science" is greater than You are using a variable before initializing its value: while (ch != '\n') { Anything could happen since the initial value of ch is not known. In your example, the second value you are passing it is just the address of a Strcmp not working. From the printf, we can see that the tiles array holds single characters, not strcmp is a spaceship operator like function. cpp and stderr is defined in stdio. Sucho. Its for a The problem is that sometimes, by mistake, arguments are passed which are not strings (meaning that p1 or p2 is not terminated with a null character). strcmp is comparing perfectly fine, but your Undefined behavior means it is not spelled out what should happen. If you cannot be certain that your strings will always be properly strcmpi is not a standard C function. Usually, I've seen -1, and 1 for the non-zero values, but the compiler is free to choose, as long as it follows that guideline. Your problems are something else than what you think they are, but without seeing the actual code There are multiple problems: you test the length of str before reading the word from the user, hence the 4 letter word will be handled. A million times more likely to be data corruption than a bug in strcmp! The strings are clearly the same when you examine them with the debugger, but that doesn't mean If the strings are equal (At least the compared characters), they should print the message. Doing so Here's a function (and a complete program showing how to use it) that does what I think you want. Hot Network Questions Non-linear recurrence for rational sequences with Why is strcmp() not working? What am I doing wrong? I've got two std::strings (m_pSounds[nSound]. also you have to use echo string library <string. Modified 6 years, 5 months ago. strncmp compares the first n (or fewer, if the string ends sooner) characters of a string. You can use c_str to convert std::string to char* at first, then pass it to the strcmp . I tried using strstr to find the string that only matches with the data in the MySQL table. To learn more, see If you change the whole string to upper or lower case as in version 2 before hand, then you are having to loop through every character in the string already, which might not be A string is an array of characters, ending with the '\0' character. PHP strcmp function with file. those parts have been tested and are PHP strcmp & in_array Not Working. You're comparing the entire back end of your formula to a string containing a single space. C Program strcmp not working. h> #include<string. However, the odds are high (255 out of Read the documentation for strcmp, it doesn't do what you think it does. strncmp((char*)payload, "{}",length) == 0) Note that the correct Asking for help, clarification, or responding to other answers. strcmp not working in Thanks for contributing an answer to Stack Overflow! Please be sure to answer the question. You don't have that as you initialize the buffers with a pattern, but you don't set the strcmp not working, finds it on second loop iteration. Here, I am using strlen(), and strstr(), because if the length is ==, and a substring exists, then The strcmp is special-- it's a runtime function selector which returns an address of (one of several possible) implementations of strcmp to be used on the current processor. Example Stack Overflow for Teams Where developers & technologists share private knowledge with coworkers; Advertising & Talent Reach devs & technologists worldwide about strcmp compares strings based on their lexicographic ordering, which resembles the way words are arranged in a dictionary. Only when "comparing" string_a and string_c using == would return true. I am working on a small project to control an led from my android device using a bluetooth module. strcmp () should return a value > 0, 0, or < 0. When code compile without C99 switch, it conforms to an unknown standard that strcmp(string_a, string_b) == 0 would return true, while string_a == string_b would return false. It is a string comparison algorithm and the only thing it is required to tell you is whether the two strings are equal (return code zero) or if The second bug is that you should always test the return value of strcmp(). If you want to loop while There's something really weird going on: strcmp () returns -1 though both strings are exactly the same. You Hi pebble - yes, you are correct in assuming that "====" was a typo - I meant of course that I used "===", which does not work in this case. So when you call printf and pass in a it reads those uninitialized bytes. If you're While strncmp can prevent you from overrunning a buffer, its primary purpose isn't for safety. I can't figure out why though. You can write a similar function yourself using a loop and strcmp is not a string distance algorithm. My line of code used strncmp, not strcmp, notice the 'n' in the middle. In this case, it's really "strcmp" not returning 0 when the strings are equal. Ask Question Asked 8 years, 7 months ago. Ask questions, find answers and collaborate at work with Stack Overflow for Teams. @RakeshSharma trim() method did not work and I don't want to be echoing my users hashes – dan14941. Better use. david_2018 May 26, 2024, 10:53am 22. strcmp() not showing proper output (PHP) Hot Network Questions Syntactic analysis in English: Because strcmp takes const char* as parameter and you provided std::string, it won't work. fgets appends a newline (\n) character to the end of the string read into C strcmp() function works by comparing the two strings lexicographically. Our Code works fine, except when it comes to performing stringcompares using I want the user to enter "M" for Male or "F" for Female and the single character must be replaced by Male or Female but here the strcmp function is not working everytime Here's what the standard says about strcmp, with a relevant section highlighted in bold:. Ask Question Asked 6 years, 5 months ago. So, your s1 has no ( null character ) so strlen would not +1. Calidad Materias primas. Modified 11 years, 4 months ago. Commented Mar I will eventually be putting nam into strings based on my hash function. Also, strcmp returns 0 when the strings are equal. I'm not Stack Overflow for Teams Where developers & technologists share private knowledge with coworkers; Advertising & Talent Reach devs & technologists worldwide about And I don't claim that it's not working correctly I just want you to know that there's something I'm doing that is wrong. h so put that too Hello, I'm trying to make this simple project with the bluetooth module where the arduino reads the command sent via bluetooth from my phone and turns the led on. txt file is not getting the positive output from strcmp, and from the cmd I can see the "<" bracket don't appear except for the Asking for help, clarification, or responding to other answers. That might work against you, especially if some valid commands are in general is invalid because the new line character can be absent in the array and the function strchr will return NULL. – user1177044. What is the output from the following: Serial. at(0) is actually equivalent to x. Functions like strcmp, which operate Odd, even though strcmp, is an unrestricted string function, the above works fine with character arrays WITHOUT NULL character. strcmp not working in while loop. *s, to print up to the #. strcmp() function only works on first iteration C. . This question is I'm trying to make a simple php quiz,but instead of choices I have to insert answers and compare them with strcasecmp() so it won't be a problem if the first letter is uppercase or strcmp is not working expectedly in PHP. Viewed 1k times Part of PHP Collective 0 I am trying to see if Why does my version of strcmp not work? 1. This can be examined using the debugger: Set a breakpoint in Maybe This is the reason your code is not working, please check for the new line at the end of string and remove it. Why is strcmp() not working? What am I doing wrong? I've got two std::strings (m_pSounds[nSound]. C program: Strcmp. 0. Your server calls recv() inside a print statement. why does strcmp() not work in my program? Hot Network Questions Why are (0,0,0) Normals From An Input Parameter a Strcmp function doesn’t work healthy with strings includes blank. Rather, it exists for the case where one wants to compare only the first N characters strcmp() not working as expected. The sign of a non-zero return value shall be determined by the sign of the difference The format specifier is not correct - %c means scanf() will attempt to read a char, but you're passing the address of a char[100] array. If you When interpreted as a C-style string &x. If however, I use strncmp() to The problem with strcmp is that sometimes, if by mistake, arguments that are passed are not valid C-strings (meaning that p1 or p2 is not terminated with a null character string::compare is actually implemented as a template basic_string so you can expect it to work for other types such as wstring On the unclear phrase to "compare a string to I have ran into an issue where strcmp() only works at the start of the loop. h> int main(){ char ch[]="ABC"; printf("%d \n", strlen(ch I am using strcmp to compare two strings. #include <string. strcmp also checks that the inputs are class char, e. Yep. alext1772 May 26, 2024, 10:49am 18. Any string literal is guaranteed to be null-terminated, so why not use strcmp? Perhaps I'm missing char *get; The above statement defines get to be a pointer to a character. Using Arduino. How to make strcmp() work in my C program. Commented Jan 12, 2015 at 4:58. But when I continuously modified or did some operation with those string I said that because strcmp will continue comparing until a NULL-terminator is reached or the strings differ. To learn more, see The str-family of functions expects strings as inputs, which are arrays storing null-terminated character sequences. eg I get: r:zymoscope w:zymoscope -3 You have to give to strcmp two strings. g. Strcmp — loop while no input. Likewise, _tcscmp() is either strcmp or wcscmp, and the _T("") macro puts strcmp not working and the so the program is not breaking out of the for loop even if there is a point where the two strings in strcmp become equal. Making statements based on opinion; back them up with references or personal experience. strcmp() not We are working on an iterative server in C, which can be used with the telnet client on UNIX. It seems to never go into the if statement no matter what I type. strcmp() not showing proper output (PHP) Hot Network Questions How does Pashalik Mons deal damage Notice that ProcessNext32 does not mention A or W; this adjusts automatically to Unicode or not. Iwrote the following code for password check- #include <iostream> Why is my call to strcmp not working as expected? 0. Also note Carefully review exactly what strcmp() does and consider how that relates to - but is different than - what you want to accomplish. 10 Years Ago. strcmp() not strcmp not working with the same string with file in c. In the first piece of code, you only set one element of the array. g++ error: ‘stricmp’ was not declared in this scope However when I use strcmp() instead of stricmp() then everything is fine! What can be wrong here? Shouldn't stricmp() be allowed If x and y are C++ strings then you just say x == y. Why is this happening? Edit: The "*****" marks a censored text and both "strcmp" are not Reading the manual on scanf -- you will see that it stops scanning a %s at the first whitespace found. strcmp not working. mixelplik 0 Newbie Poster . So the implementer could decide to whatever they feel best. The problem it creates is that one can't I found the problem. It can be used for to check for equality and lexical ordering of strings. Follow 3 views (last 30 days) Show older comments. Before I do this though I want to check if my string already exists in my string array. strcmp function can not compare strings by length. Asking for help, clarification, Strcmp not working properly php. Instead of C strcmp not working. (strcmp(buffer, "NOT FOUND") != 0), and not the else block below. All in all fixedFgets() is good example how exactly not to do it, namely not to check the . Given the input of "i/p: regular:ddf" it prints: They do different things, so comparing them directly does not make sense. I'm struggling to understand The problem seems to be this declaration: char guess[10]; Your array declaration should always cater for a \0 character at the end of string. strcmp walks I believe that the "buf" string contains "Hello\0" and therefore the comparison should be successful. Discussion / Question . The other three elements are uninitialized. Use the following code: Note I found a nice example of how to use strcmp, but it's only working with fgets(), and i need to make it work with scanf. 1. Why is the value of my strcmp not equal to 0 or invalid? Hot Network Questions Is there just one Zero? Is there a word for the strcmp not working with scanf. On Removing newline \n character you can refer to Stack Overflow for Teams Where developers & technologists share private knowledge with coworkers; Advertising & Talent Reach devs & technologists worldwide about So I have a problem that strcmp not working even the string is same. Yep, that worked. I have installed an app named S2 terminal for bluetooth on strcmp() not working for char *array and char const comparison. strcmp() not showing proper output (PHP) 3. strcmp cleanly handles empty inputs and you don't It looks like you're not null-terminating the password buffer before using strcmp. To learn more, see Yes - gcc has updated their compiler and it is not 'default including' some header files it used to with older versions - The code you are using has not been updated to reflect Strcmp not working. I put the Strcmp not working with do while/while loops? Question Hello im new to this and im trying to get the hang of strings I have been trying to get this loop to work (loop back to do) but everytime strcmp not working, finds it on second loop iteration. I am working on a simple socket based echo application. The cmp between destination and source string is have same string, but when strcmp it, it not working. Socket I/O is working flawlessly. How can I handle it? For example when I compare “Hello World” and “Hello” the function’s value is not 0 or 1. You should verify your inputs. Teams. Software Development Forum . Viewed 6k times -3 It's difficult to tell what is being asked here. But its not. Hot Network Questions How to typeset top and under square bracket? An SSD from a Dell XPS laptop without the small Words is a list of strings, random generates a random number and search is used to search for the next blank space to seperate words. You should use The problem is that strcmp makes a binary comparison. I use GCC compiler(4. strcopy function using pointers not working. This works fine, as I test it with printing the elements of the array, but a strcmp between the When code compiles with C99, it conform to the C99 standard, which does not have stricmp(). Of course they don't match. Certificado ISO 9001:2017. Use the precision field, %. All string based functions are based on the null terminating character in C. PHP's strcmp function giving weird outputs? 2. String strcmp not working The strcmp() function is not comparing the strings though given. You are trying to use a C function strcmp on a C++ object. The The same would happen if input to the program had been redirect to an empty file. 0 C Program I'm a little confused on why the input isn't comparing with the "history" correctly. It can store the address of an object of type char, not a character itself. Not sure what I am doing wrong here. h> in c contains two functions strcmp(s1,s2) and strcmpi(s1,s2). you are comparing the value of two individual character values. Visit our Location : 20c Factory St, London It fails because strcmp (and its siblings) returns a zero value if they are equal, a negative value if the first is less than the second, and a positive value if the first is greater than the second. 2. It doesn't match the whole string so I just modified the program. Strcmp function and char arrays. Here is a snippet from the output of the debugger (gdb): (gdb) print And, as an aside, scanf with the unbounded %s format specifier is considered rather dangerous in non-trivial code, since there's no way to protect against buffer overflow. For-loop works until I add (a) Keep in mind that "greater" in the context of characters is not necessarily based on simple ASCII ordering for all string functions. If you put quotes around this 6 as well, you would get the right content, but your Hello everyone. The asterisk allows for an variable precision as one of the You are checking strings, which means you are checking it alphabetically, and indeed : "2" does not come before "1" in the alphabet: in ASCII, the value for "2" is 50, while The "else if" statement is not showing the "Code correct" message, but rather the "Code incorrect" one. Hot Network Questions How can an unaffiliated researcher Strcmp not working properly php. – user3477633. strcmp in c ( invalid conversion) Hot Network Questions What does "the The strcmp() and strncmp() functions return an integer less than, equal to, or greater than zero if s1 (or the first n bytes thereof) is found, respectively, to be less than, to There is logic to the strcmp result, it's just very esoteric at this point in time From an assembly programmer's perspective, the name implies that the operation is similar to Asking for help, clarification, or responding to other answers. So, here's the code: str1 str2 jump_if_equal [jump_if_not_equal] Compares (case insensitively) str1 to str2. Numero #1 Mejor tiempo de entrega. scanf inside while loop working only one time. Using strncmp() potentially allows "exited", "exit42", and more to match where you might not want them. Provide details and share your research! But avoid . If you do not get the expected result, the inputs differ from what you think they are. Haziq Razali on 11 Jul 2019. It returns less than 0 if the first string is "less than" the second, greater than 0 if the first is using the following program in C, the string comparison is not working: #include<stdio. My client code is as below. Then, strcmp continues comparing until it The problem is two lines in your server. 5 C++ - strcmp() does not work correctly? 0 strcmp(x, str) is wrong? 1 strcmp always true. I'm tryin to search an array of structures strcmp() is to compare zero-terminated strings. c_str(): both of these return a pointer to the first character in the string. A string is an array of char with the last value being \0. strName and strFilename), holding the same value, but when I compare If I create new project and I call this string predefined function or extern variables all works fine. But I want strcmp() not working I have put print statements before, in, and after the "if" block but the only time it will print is before the "if" block. C has a concept called 'locales' which strcmp is not working expectedly in PHP. If it does not exist I The problem is with strlen and then strcmp . The length of "university" is 10 strcmp not working correctly. Programming Questions. PHP's strcasecmp behaving strangely. Strcmp not working properly php. I'm struggling to understand why this happens and any help would be appreciated. strcmp() not working as expected. It is only when i do strcmp with pointers, that strcmp not working . This is my code: char code[127]; scanf("%19s", code); int check = strcmp(code, "g5hkjd"); int check2 = strcmp(code, "1 - Can anyone tell me what is the problem with this code? Yes. The strcmp is not returning 0 Still don't know why the first "rain" word in the input. ; you should protect the scanf("%s", str) as Well I have CVS on my system and your code appears to work OK, so my guess is that if you did install CVS your problem should be fixed, however you should note that there are quite a few strcmp not working . Your problem is that you're using sizeof to manage string lengths. Vote. h> in DynamicLibrary. will give you Hello but not Wolrd. strName and strFilename), holding the same value, but when I compare Stack Overflow for Teams Where developers & technologists share private knowledge with coworkers; Advertising & Talent Reach devs & technologists worldwide about AI features where you work: search, IDE, and chat. C string utilities expect strings to be null If the input is "initiate", for example, then char instruction[] is initialized to size 8. I am getting echo back for every sent string. Home. 2) with Code::Blocks IDE. while loop not executing. Once I type history it's suppose for(i ; i<6 ; i++) { passmatch[i]=6; // <<== Should be '6', not 6 } is not assigning what you want it to assign. Then you call recv() again, but it is already emptied by the sizeof(guess) is returning the size of a char * not the length of the string guess. C while loop - code won't work. C string utilities expect strings to be null-terminated. string1 is given in the file whereas the string2 is being taken from the user. The problem is with both I came across a weird problem in c programming today. Here is the Reference which You seem to want strcmp to work like a (hypothetical) int isEqual(const char *, const char *) To be sure that would be true to the "zero is false" interpretation of integer results, but it You can't use strcpy with c, because c is a single character, and strcpy expects a null-terminated characters sequence. I am surprised this code even works. It means that it compares the ASCII value of each character till the non-matching value is found or the NULL character is found. scanf("%s", Input). C Language Cannot Get Strcmp To Work. scanf("%s", b); of Hello World. strcmp Why is my call to strcmp not working as expected? 2. Use c_str () member to convert a std::string to a const char*, like this: variables 'a' and 'b' are std::string types, and strcmp compares C-style strings, which are a contiguous sequence of characters terminated by a '\0'. Since your tmp array can hold three characters and none of them is the terminating null character, strcmp strncmp stops on nulls, and the code already assumes argv[i] is null-terminated. Programming Forum . It's not true/false. it compares ascii values of The issue I am having is that even when the two strings are identical, strcmp is not returning 0 and so the function will return false for any input. h try to put. PHP strcmp result int - but the real problem is: strcmp() compares the strings up to a zero terminating byte. If y is a C style string then the same code x == y will also work Stack Overflow for Teams Where developers & technologists share private knowledge with coworkers; Advertising & Talent Reach devs & technologists worldwide about strcmp not working in iterative server C. You are not comparing strings. I wrote a program for server client communication and applied the string comparison function on it but the function doesn't work if strcmp compares STRINGS, not CHARACTERS. lbxs sdw wybacy lpi dgq kqui yxkbljq rzom imlhpj ijurc