How to scan a string with spaces in c. scanf function doesn't scan properly.


How to scan a string with spaces in c And what I need to do is to split this sentence First of all, %s in scanf() expects a pointer to char, not a pointer to pointer to char. #include Thanks for the info, i was not aware of the function. Since / is not white space, it gets included in the string bit, as does the 17 for the same reason. Since you just want what the user entered without parsing, you don't It is possible to read string with spaces (via scanf() function) by using ‘scanset’. I can't see a reason why sscanf() would ever return anything other than zero as long as p is not a null pointer How can I read a string with spaces in it in C? 0. Yet if OP insists on scanf(). h> C Examples C Examples C Real-Life Examples C Exercises C Quiz C Compiler C The >> operator will drop leading white space read the target object using white space as a delimiter (so for standard PODs will stop reading the target at the first space). h> C <math. For the purpose of this assignment, a "word" is defined to be a sequence of non-null, non-whitespace characters, Stack Overflow for Teams Where developers & technologists share private knowledge with coworkers; Advertising & Talent Reach devs & technologists worldwide about In C, the lexical analysis phase is the first phase of the compilation process. Problem with reading string inputs with scanf: We Use fgets() (which has buffer overflow protection) to get your input into a string and sscanf() to evaluate it. Some people might I was asked to do a work in C when I'm supposed to read from input until there's a space and then until the user presses enter. Structures and Strings in C. c reading separate words from text file using fscanf() 1. Using fscanf for reading C- Scanning a string and assigning it to a char* within a struct? 1. But, when I type the space while the program is If you enter a string of more than 9 characters, the behaviour of this program will be undefined. You don't actually need spaces before most % conversion specifications (%c, %n and %[] are the Scan a string including spaces in C 2 Is there any way to use fscanf to read in the following white space? 0 How do I read in white spaces with scanf? 0 Read whitespaces with fscanf 1 Ignore I am trying to have my program take a name as input from the user and then print out the initials of that name. h> C <string. Scanln, bufio. h> C <ctype. tommy brown --> tb What I have so far is this: int main (void) { We can take string input in C using scanf("%s", str). Read a String with spaces till a new line in C. Improve this answer. Append a If there are blanks at the start of the second field, they'll be eaten by the \t in the format string. Share. It is incredibly hard to use the scanf() functions +1 clever. The char *gets(char *str) function included in the C library will read a line from the standard input (stdin) and save it in the string referred to by str. And if spaces are detected the next word should be printed in the next line. In order to read space-separated Since strings are not built-in data type in C++, So we use #include<string> use string class in c++ program . There are 4 Brother, you have decleared char array as char n[50]; which can store only maximum of 50 charecters as a string at 'n'. reading Use gets() in scanf to Get User Input With Spaces in C. Now I am trying to get input from users, which may have spaces. Then allocate char* cptr and get set cptr to begin of Coming to your question: The question is to find spaces between the string. In your case, the starting token will be from "-" and end with It will read until the end of the file/string or a white-space, so it won't actually stop reading at the closing double quote. The s The C language's scanf() function reads formatted input from stdin, allowing for selective input parsing, while fscanf() reads formatted input from files, both with similar time How to take user inputs with spaces in C: In this post, we will learn how to take user inputs with blank spaces in C. 21. This is not a good thing, You are using a wrong function to read integers: in spite of returning an int, function fgetc is reading individual characters (why getchar returns an int?. You can use getline (POSIX 2008 may not exist in your system) that conveniently manages I have to scan a string with spaces so I can do somethings with it in this case moving the string n chars to the right or to the left. That's okay in theory. From scanf manpage: s Matches a sequence of non-white-space characters; the next pointer must be a pointer to character array that is long Put spaces before the literal characters in the format string for scanf(). ) Or you could use fgets, There were still spaces in array_c, so I tried " %c ", and it worked! I want to learn of another way to get characters with spaces. In fact, gcc warns me with your format string: You can use the set notation to specify a set of allowable characters in your name, and explicitly allow spaces: scanf("%d %[ a-zA-Z]", &id, fullName); Here, [] specifies a set of I am facing problem in printing a string with whitespaces. But, it accepts string only until it finds the first space. And what I need to do is to split this sentence scanf will stop reading when it hits a space. */ Scanner(); /* * Destructor: ~Scanner * Usage: usually implicit * ----- * The destructor deallocates any memory associated A better option would be to use bufio. Well you can provide space between '%d' if you are printing integers. As I have suggested in The %c conversion specifier in the format string of scanf does not skip (read and discard) the leading whitespace characters. So change its declaration to. (3) use strcmp or the equivalent on the first word to decide In C++, string find() is a library function used to find the first occurrence of a sub-string in the given string. I know I can get one value by doing: scanf( "%i", &amp; The %c conversion specifier won't automatically skip any leading whitespace, so if there's a stray newline in the input stream (from a previous entry, for example) the scanf call How to Take Input of a String With Spaces in C? There are various methods to input a string with space and accept it in C: Methods to Accept String With Space in C. To read any kind of value like integer, float, character we use cin, cin is the I'm trying to write a code for a function that takes an empty array of pointers and its length n. As we know that, scanf() stops reading of the string as soon as a How to Read a String with Spaces in C Let's see what happens when you read string using scanf. We declare string variable as string s; and take input as ‘cin>>s’ Since this question is returned by searches for "how to read a string with scanf", it might be appropriate to point out that this question is about ways to pass the pointer to the The problem with your code is this: when you read the first char (a), you press enter (\n) for insert the next char, so now on stdin there is a \n that you haven't readed. If your array of characters has spaces, you can use fgets. Here is a simple program to demostrate what happens with scanf when you try to read string Taking String input with space in C (4 Different Methods) We can take string input in C using scanf("%s", str). Follow answered Nov 9, 2011 at 16:33. For length calculation of whole string, We can use a flag You can just include the commas in a scanf format string:. 0 Tennis B 1. /gets Enter a string with spaces: Skill Vertex You entered: Skill Vertex [root@centos If you're building a CLI tool I highly suggest you check out cobra. copying The * in scanf ("%*[^\n]", first_line); tells scanf to scan but not store the scanned string. Members Online Implementing General Relativity: Rendering the Schwarzschild black hole, in I'm not good at using C language. If you have a leading whitespace character in the Since this question is returned by searches for "how to read a string with scanf", it might be appropriate to point out that this question is about ways to pass the pointer to the Problem scanning strings with spaces in C. It would be kind to show how to isolate the words. Ignore space or newline when reading a line. The problem with getline is after i scan 't' (testcases) using cin>>t,the compiler is expecting me to If this is a teaching project and you're still using scanf, %s should do. How to scanf multiple inputs separated by space in C? The "%d" and "%f" will happily handle numeric text separated by spaces, tabs, end-of-lines, etc. When you try to scanf() the input, you're writing past the end of your three-character buffer ch. The only working solution using scanf and family is the Also, a single whitespace character in the format string can match any amount of whitespace. %[^\n] scans an entire string up to Don't use scanf like that. Or add a \n after the ]; or, indeed, a space would do. So the reason why "%d /%d" is best is that it contains the minimal amount of whitespace required I am writing a C program in which i want to scan an user given input like this: "Hello how are you" (One single line without quotes) and then each of this word should in an user Therefore, there's space for only 2 characters. But stdin with a keyboard with 105 keys are not formatted input: The user can key anything in. "hello world". To read string with space you can do as follows: char name[30],ch; i=1; while((ch=getchar())!='\n') { name[i]=ch; i++; } i++; name[i]='\n'; printf("String is %s",name); Use RegEx in scanf to Get User Input With Spaces in C. Note that I used this lines to scan a string with space scanf ("%*[^\n]", first_line); printf("%s\n",first_line); But it doesnt work!!! What to do? Stack Overflow for Teams Where You can't do this work with the sscanf function and a "central" string with an arbitrary number of spaces in it, since the whitespace is also your delimiter for the next field; if These are 2 ways to read strings containing spaces that don't use gets or fgets You can use getline (POSIX 2008 may not exist in your system) that conveniently manages C get string with spaces, of unknown length, with fgets 3 Reading strings with spaces from a file 0 How to accept space in string in C in the given code 0 Loop a scanf while I think by default values read by scanf with space/enter. By default scanf reads the string until it reaches a whitespace. When Discussions, articles and news about the C++ programming language or programming in C++. One gotcha though, is that fgets will read and store You probably don't need the format string to be so complicated, either - "%lf" should work just fine to read a double. when I scan in the first char in the string in my while loop condition statement, it is doing this but when I scan in the actual string I've included the "%*c" to read but discard the new-line. As you want to store 'a' strings; you would have to For reading a string value with spaces, we can use either gets() or fgets() in C programming language. By The problem is: I need to read a string from the user, but if he types just a space, I need to print a space. But I would like the user to supply all 4 ints at once instead of 4 different promps. Here is my dumb question. The scanf() function reads the Reading in a string with spaces in C. You can use the scanf() function to read a string of characters. str is a c-string which is not altered (it can even be a string-literal). I mean number of testcases. They are rarely necessary since while ( scanf ( "%c", &x ) == 1 ) Using %c you can read whitespace characters, you must only read all data and store in array. it reads the character until a blank space is found. , yet not distinguish between spaces scanf (and cousins) have one slightly strange characteristic: white space in (most placed in) the format string matches an arbitrary amount of white space in the input. char str[25]; And you cannot use scanf to read sentences--it stops reading at the first If you want to scan to the end of the string (stripping out a newline if there), just use: (zero or more), then the literal string "cool", then whitespace (zero or more) again, and then finally a I am trying to read in a string that may or may not include spaces ex. This is just a Change: scanf("%s", &array[i]); to this: scanf(" %c", &array[i]); since what you attempt to do is read your string character by character. The simple solution is, COUNT THE WORDS and keep a variable with that The fundamental issue is you are loosely using 4 definitions of string. Is there a more sophisticated way? c; input; scanf; I'm making my first "big project" in C and I'm currently working on the registration/login part. . starting from any one of the delimiter to next one would be your one token. If you want to do it using C++ IOStreams I think the nicest to use option is to install a strtok() divides the string into tokens. How can I use scanf to get input from the keyboard? #include These are 2 ways to read strings containing spaces that don't use gets or fgets. Using scanf, I have to print the full line, i. a); //where name is the object fgets() is the right tool. One character space is saved for the terminating null byte to mark the end of the string which is added by scanf automatically. Strings are acquired using the fgets() function, so dest and text can have "dynamic" length (from 1 "rescan every string to remove the spaces will increase the computational time a lot" - no it won't? You just need two pointers, a source and destination, and you can do this in It will read until the end of the file/string or a white-space, so it won't actually stop reading at the closing double quote. For example: If I give n = 1, the string. I want to scanf multiple numbers and put them in an The scanner * starts empty, with no input to scan. NewReader and its ReadString method. This function is used for parsing the formatted strings, unlike scanf() that reads from the input stream, the sscanf() To my knowledge it's not actually possible to see if a string contains spaces without checking if every character is a space, it can't be done any quicker, except when you find a I need to write a function that will count words in a string. Any white space in the format string eats any white space (including newlines) in Taking String input with space in C (4 Different Methods) We can take string input in C using scanf("%s", str). scanf(“%[^\n]s”,&arr); By using ^ we are telling that while writing a string, the time when we Just adding some more explanation to the comments, when you do: cout << "Enter value:"; cin >> x; The cin instruction is executed when the user presses Enter, so the input [root@centos-6 C]# . 8k 13 13 gold In C, sscanf() function stands for "String Scan Formatted". scanf function doesn't scan properly. There are 4 methods by which the C program accepts a string scanning string in c. My name is James. 1. Here, we will see what is the difference between gets() and fgets(). One gotcha though, is that fgets will read and store Whereas in 2nd case by writing s we are allowing a string to be taken as input. How do I read user input across multiple lines, spaces etc? 0. By doing the following with a number select menu that is inputted by the user. You will An important thing to note here is that c++ style strings can be accessed like an array, meaning rawInput[0] is the first character in the string all the way up to rawInput[length - 1]. Reading spaces in C. 3. There are 4 methods by which the C program accepts a string with space in the form of user input. Adrian Cornish Adrian Cornish. Let us have a You can use the same trick used for strings, note that your question doesn't appear to ask for that. Hot Network Questions Can quantum computers dest is a string that cannot contain spaces, unlike the other fields. 23. int blinky, pinky, inky, clyde; scanf("%d, %d, %d, %d", &blinky, &pinky, &inky, &clyde); Here's a complete Trying to use scanf to read strings with spaces can bring unnecessary problems of buffer overflow and stray newlines staying in the input buffer to be read later. Anticipating the next question: inspite of reserving space for 10 chars we can only But any leading/trailing spaces will be in your string. /scan-set Enter a string: Skill Vertex You entered: Skill Vertex Another scanset example with ^ [root@centos-6 C]# . Alternatively, I wrote a quick If you want to accept 1c2 and 1 c 2 (and also 1 \t \t c \t 2 etc), use the pattern with the space: scanf("%d c %d", &x, &y); Here the format string %[ \t] would mean "read a string strp (pointer to string) is the address of an already allocated, non-constant c-string, to be tokenized in-place. It is a structure of data which is supposed to be written in the FILE. Reading multiple I want to read a substring from a string which contains integers as well as a string with spaces, such as this: 1 2 I'm gonna make him an offer he can't refuse. %s reads a whitespace-delimited string with scanf, so if that's not what you want, it's not the thing to use. I don't want to use array like, char names[50]; because if the user gives string of length 10, then the remaining spaces are wasted. Here, the fscanf first scans a number(%d) and puts it in p. One more point to note here is that “%s” does not read whitespace characters (blank space, . If you don't care about leading spaces, a space before the % would work, too. The file contains: AAAA 111 BBB CCC 2222 DDDD EEEEE 33 FF The code is: int main() { FILE * finput; int i, b; char a[10]; char c I'm not good at using C language. Note that if the user enters more than str is an array of 25 pointers to char, not an array of char. C provides four methods to accept string input with spaces: using `gets()`, `fgets()`, and two variations of `scanf()` with scansets. I know i can change the %s %s to %f %d and it should compile fine, but I'm being You probably put a space in between "Ben" and "Parker" in input. Let's take a look at a simple example that shows the how to use this I want to read input from user using C program. Reading space separated inputs into multiple variables with scanf in a loop. gets() is often It seems that the solution to this is, indeed, a lot easier using scanf("%[^\t ]", buffer). If we pass the i actually need to scan the integer also(3) . It displays book. A new-line is considered white-space, which is treated specially in a scanf conversion string. If I do this: scanf("%2000s %2000s", a, b); It will s: matches a sequence of non-white-space characters. That's also indicated by the fact that So you are only allocating space for three characters in ch. With fairly minimal changes you could try using the string-scanning modules from Dave Hanson's C This uses %c to read single characters; it uses %16c to read the multi-word street address and %11c to read the (possibly multi-word) city. And scans n strings of max length of MAX_LEN (a defined constant) until a new line Stack Overflow for Teams Where developers & technologists share private knowledge with coworkers; Advertising & Talent Reach devs & technologists worldwide about Explanation : Here [] is used as scanset character and ^\n takes input with spaces until the new line encountered. scanning a line of strings with spaces using scanf. In this step, the lexical analyzer (also known as the lexer) It takes a string and two two integer values: start and end. In your case, you only have one argument, which is not set because of this. 0. In this: scanf("%lf",&b); scanf("%[^\n]s",string_2); The first scanf reads a number from the input, but has to wait for your terminal to give the program a For reading a string value with spaces, we can use either gets() or fgets() in C programming language. It's written in pure go (see dependencies) and used by multiple well-known projects. I tried scanf("[^\n]s",name. This would cause the cin logic to believe it had an answer after seeing the space following "Ben". As it Fact is that these functions were written to consume tabular data, like CSV files--- Hence the name: scan formatted input. Reading character and integer separated by spacer in C. Then, it scans a comma(and discards it) and then scans a maximum of 39 characters or until a comma and Scanning a string with spaces from a file while also scanning numbers before and after it in the same line. /scan-set Enter a string: GEEKs_for_geeks You entered: GEEK. It cuts the string from the You should note the C++ stream library automatically reads and decodes int from a space separated stream: int main() { int value; std::cin >> value; // Reads and ignores space If you literally need to know if the "string is blank or full of an undetermined amount of spaces", use LINQ as @Sonia_yt suggests, but use All() to ensure that you efficiently short Output: Note: The & is not used in the case of string reading because the array name is a pointer to the first element (str[0]). If first character of scanset is ‘^’, then the specifier will stop reading after first occurrence of that The trouble is that once you've read to the first newline, the next character is a newline, so the scanf() reports that it was not able to convert anything (return value 0, not +1 clever. A normal character would In this chapter, we will learn how to read a complete string with spaces in C++? Read a string with spaces in C++. (Although your user will then be limited to passwords not containing spaces. Please notice the space before %c, The trailing white spaces in scanf() format strings are a UX disaster if there is ever any chance that the input could come from the keyboard. 1) text file lines that are terminated with '\n', 2) grouped of characters separated with "space between scanf will stop reading when it hits a space. I would like to make the user insert an efficient password, asking him to Stack Overflow for Teams Where developers & technologists share private knowledge with coworkers; Advertising & Talent Reach devs & technologists worldwide about @chux-ReinstateMonica, The OPs original format string will not allow the call to fscanf() to return until the first non-white space is encountered (most likely at the beginning of the next line of data. 2) Scan in and save an unlimited number of non-white-space char to answer. It uses %7s, %9s, and %2s to prevent I just ended up writing these codes. I can't see a reason why sscanf() would ever return anything other than zero as long as p is not a null pointer Please, help me to fix some problems. id fine but it only Stack Overflow for Teams Where developers & technologists share private knowledge with coworkers Advertising & Talent Reach devs & technologists worldwide about You are using the wrong type of argument passed to scanf()-- instead of scanning a character, try scanning to the string buffer immediately. h> C <stdlib. , then I have to get the length of this entered string and store it in an int i. How to read a string with Can anyone give the code for this structure Demo where a and b will contains string with different words[white-spaces]. Approach 1: How to use scanf with a different format specifier: We can use the scanf function with a different format specifier to read strings with spaces. i. What is wrong with the following code and how can i avoid it? #include <stdio. The string I need I am having difficulty getting the program to end. how can I scan spaces using scanf but how to scan the initial spaces entered in a string? char buf[100]; // Scan up to 99 non\n characters The newline will be left behind in the input stream, but the %d conversion specifier automatically skips over leading whitespace characters. The only working solution using scanf and family is the If I don't know how long the word is, I cannot write char m[6];, The length of the word is maybe ten or twenty long. scanf("%d %d %d", hi so this is what i have to do: Every line has: Id: An integer between 1 and 10000 Name and surname: at most 50 char including English letters and digits and space. 1) Scan in and toss all leading white-space including '\n', ' ', '\t' and a few others. What I normally do is (1) read whole lines using fgets or the equivalent, (2) break up the line into whitespace-separated "words". Leave out sizeof() and simply say: You're running up against the limits of what the *scanf family is good for. %c reads a single character, but does not skip whitespce, so you I am using scanf() to get a set of ints from the user. code. Unlike fmt. The point is that i do not know if i do need to use it since i want to get input from files, print out the words on screen and other file and [root@centos-6 C]# . h> int main() { char str[50]; int t Possible Duplicate: Dynamic String Input - using scanf(“%as”) strcmp with pointers not working in C Is the following considered good code? Shouldn't I have used malloc Trying to use scanf to read strings with spaces can bring unnecessary problems of buffer overflow and stray newlines staying in the input buffer to be read later. Scanset is represented by “ %[] “. I I'm actually new learner so I got a bug while learining , I'm actually trying to fscanf from file then display it on the screen everything works fine until i add name of a book with space in the file. I will show you different approaches with drawbacks. It halts either when the I n this tutorial, we are going to see how to use scanf() string function in C. (So Note the leading space in the format string, to tell scanf to skip white-space (like the newline from the previous line), and the width-specifier to not read more than can fit in I'm trying to scanf multiple ints from a string, but I don't know how many it will have, because it varies from case to case. How to scan a string with white spaces in structure members in C? 0. NewReader with ReadString allows you to read an entire line of input, Im new to C programming and want to scan a float and int but as a String for one of my labs. Quoting C11, chapter 7. fscanf a line from file in c. 0 etc (I need the letter and This is the right behaviour. 6. Always C Reference C Reference C Keywords C <stdio. Also same for other cases. Nothing else can be used. 2 / p12, fscanf() (emphasis mine) s Matches a sequence of non I need to read all the information from a line in a file before a space and store it as a string, how do I do that? File example: Biology A 4. This %[] is a scanset specifier, and using 0-9, a-z, a space and A-Z signifies that only those characters may be used as input. e. gets() is often Example if user enters: My name is James. I want all the strings to be entered by the user with spaces in between. bseeb hbw hbsejc hmrwa onxlu mjnpha mwyvy ykesxrl amjln ovrt