Wait for press enter in C inside a while loop?
If this code (with additional fflush) #include <stdio.h> #include <stdlib.h> int main() { int choice; while(1){ printf("1.Create Train\n"); // print other options printf("\nEnter Your choice : "); fflush(stdin); scanf("%d", &choice); // do something with choice // ... // ask for ENTER key printf("Press [Enter] key to continue.\n"); fflush(stdin); // option...
getchar() not working in c
c,while-loop,char,scanf,getchar
That's because scanf() left the trailing newline in input. I suggest replacing this: ch = getchar(); With: scanf(" %c", &ch); Note the leading space in the format string. It is needed to force scanf() to ignore every whitespace character until a non-whitespace is read. This is generally more robust than...
getchar() returns immediately [duplicate]
The solution is to call getchar(); twice in the end, or to use fgets(); instead. The problem is, that when you enter a char on the console, you do in fact enter an additional newline each time....
getchar() or putchar() keeps eating the first character of my input
You say int c = getchar() which will retrieve "t". Then when you say while (c = getchar()) it will retrieve "h", note that you did not even get a chance to print the character out since you called getchar in the while statement. To fix this, declare int c...
getchar() != EOF
When you type ^D ('end-of-transmission') the input buffer is flushed and everything you typed until now is sent to your program (without actually sending ^D character). It is similar to typing newline character, however, in this case the newline character itself is sent too. A program considers its input as...
C, can not read input
The problem is that you press Enter after entering a number for your scanf. The number is consumed by the scanf while the newline character generated by the enter key press resides in the standard input stream(stdin). When the execution of the program reaches the while loop: while (( c...
getchar_unlocked() explaination
The idea behind the while loop is to skip over all non-digit characters on the way to the first digit, paying attention only to dashes. For example, this code would interpret hello-world123 as -123 A more likely scenario, though, is that the author of this code fragment wanted to skip...
How c=getchar is using buffer to out textstream when I input text stream?
getchar reads character by character from the standard input stream(stdin). The thing is, the terminal doesn't flush the typed data into the stdin until you press Enter. When you press it, characters are sent to the stdin with getchar reading each character and putchar outputting each one of them until...
Kernighan & Ritchie code example confusion
c = getchar(); //read for the first time before entering while loop while (c != EOF) { putchar(c); c = getchar(); // read the next input and go back to condition checking } return 0; first getchar() reads the first time input character. second getchar() keeps on reading next input(s),...
Get just one char from long keypress python curses [accepted] [closed]
python,keypress,ncurses,curses,getchar
One normally solves this problem by setting a variable which will record the fact that a character was read reading the character if no character is available (within a timeout, for instance), stop reading if no character was read yet, record the fact that one was read (as well as...
getchar() in assembly language
If you want an ASM output you can simply ask gdb to load your C program and disassemble getchar for you. This would give something like this (on my system) : $ gdb /bin/cat (gdb) run Starting program: /bin/cat ^C Program received signal SIGINT, Interrupt. 0x00007ffff7b0c5c0 in __read_nocancel () at...
C++ do…whille loop duplicate prints with getchar function
c++,loops,duplicates,do-while,getchar
A quick fix: do{ puts("Menu"); std::cin >> option; } while (option != '3');...
How to remove duplicate output in C program?
Just change this: int lower, upper; to: char lower, upper; and this: int lower = getchar(); to: scanf(" %c", &lower); //^ Space which 'eats' remaning '\n' in the buffer ...
skipped trouble with getchar and scanf
The scanf command does not consume the Enter key that you pressed after entering y. So the getchar() happily consumes it. One solution is to consume the rest of the input line after reading y; the code for that looks like: int ch; while ( (ch = getchar()) != '\n'...
Why does getchar work like a buffer instead of working as expected in real-time
This has nothing to do with getchar directly. The "problem" is the underlying terminal, which will buffer your Input. The Input is sent to the program after you press enter. In Linux (dunno if there is a way in Windows) you can workaround this by calling /bin/stty raw in terminal...
Inputting issues with while(scanf): why does using getchar() keep the input going
In this piece of code while(scanf("Dia %d %d : %d : %d Dia %d %d : %d : %d",&day_start,&h1,&m1,&s1,&day_end,&h2,&m2,&s2)==8) after the first execution the last enter-key pressed is taken as the first character of the second scanf which it must be D to continue, and this can't be reached. while...
Behaviour of program altered by call to getchar
Your program has undefined behavior: you cannot return an array that has been allocated locally: int* returnArr() { int arr[10]; ... return arr; // <<== This is undefined behavior } The results that you see after the call of returnArr are, well, undefined: the memory returned from the function is...
K&R 1-9 // using getchar in a loop inside a loop
while-loop,eof,getchar,kernighan-and-ritchie
Okay, The inner if (c == EOF) break; avoids the subsequent putchar(c); which would otherwise be performed if that cycle of the loop was completed. e.g. main() { int c; while ((c = getchar()) != EOF) { if (c == ' ') { while ((c = getchar()) == ' ');...
String input with getchar
You have few problems there: 1) Should use %s for printing string. 2) Terminate the string with NULL terminator (It's not a string until then ;) 3) use a standard prototype for main(), such as: int main(void) ...
Exit loop when 'Q' is entered
In situations like yours, it's best to read the input line by line, and then process each line. #define MAX_LINE_LENGTH 200 char* getInput(char line[], size_t len) { printf ("Please enter your choice: "); return fgets(line, len, stdin); } int main (void) { char line[MAX_LINE_LENGTH]; while ( getInput(line, sizeof(line)) ) {...
Get whole number from input using only getchar() and convert to int
Reading in multiple characters, and determine whether positive, negative, and value: int sign = 1; ch = getchar(); //look at first char (might be a sign indicator) if((ch == '-') || (ch == '+')) //consume first char if either `-` or `+` { if(ch == '-') sign = -1; }...
*C* Acceptable 2D String input?
The char string[][] K&R notation is ancient, you ought to use the "new" char** style, indeed. Is this an okay way to input strings of digits into a 2D array? Definitely no. You are reading char by char rather than digit-string by digit-string, which I assume your intention was. Would...
Scanning values in C till hit a new-line char, '\n'
c,arrays,algorithm,scanf,getchar
You are trying to read integers as characters so once read you need to convert it to integers. Read the line to a buffer using fgets() then parse the input buffer to get integers. Store the integers to the array. The code looks like char buf[300]; int a[5],i=0; fgets(buf,sizeof(buf),stdin);...
Verify that the expression getchar() != EOF is 0 or 1 [duplicate]
The issue here is due to the working principle of getchar(). It will start reading only after ENTER key pressed, and in that case, the next getchar() (in the second printf()) will read the newline(\n) from the input buffer and won't wait for any user input. Solution: add one more...
Removing multiple blanks using putchar and getchar in C
c,string,getchar,blank-space,putchar
#include <stdio.h> /* replaces multiple blanks with a single blank */ main(){ int c; // thanx chux while((c= getchar())!=EOF){ if (c != ' ') putchar(c); else { putchar(c); while((c= getchar())!=EOF) if (c!=' ') { putchar(c); break; } } } } Your last while didnt read chars from stdin, causing infinie...
Read all data from stdin C
POSIX-compatible: yes! You're calling only getchar(), malloc(), realloc() and free(), all of which are standard C functions and therefore also available under POSIX. As far as I can tell, you've done all the necessary return code checks too. Given that, the code will be good in any environment that supports...
getchar() is giving output in C
Your program won't terminate until getchar() completes. getchar() does not complete until the input buffer is populated. The input buffer is not populated until you press 'Enter'. The character you are seeing is the character you are typing. This is default terminal-driven behavior, not driven by your program....
Secure Coding with getchar() and Whitespace Padding
If you see e.g. this printf reference, you will might notice the * format modifier, that can be used to set the field width or precision through an argument. Can be used such as printf("%.*s%*c\n", count, array, diff, ' '); This will print count characters from array, then print one...
Function to read sentence from user input
c,arrays,function,char,getchar
There you go :) void readString(char *array, char * prompt, int size) { printf("%s", prompt); int c; int count=0; while((c = getchar()) != '\n' && c != EOF); while ((c = getchar()) != '\n') { array[count] = c; count++; if (count == (size - 1)) { break; } } array[count]...
getchar() in C is completed without pressing Enter
It's not true that getchar() completes after you press enter. getchar() completes whenever there are characters to read. This difference is significant: see, for example, if you use your program with the standard input redirected to a file: $ hexdump -C abcd_file 00000000 61 62 63 64 65 |abcde| 00000005...
What is the need of using IN and OUT state in the following script?
Your version is slightly different from his one: in your program, if you have N consecutive spaces, they will be considered as N - 1 words, because for every space you add one to the word count. Also, the last input word won't be considered.
Why doesnt getchar() stop reading strings in C?
Because you have an operator precendence problem here chr = getchar() != EOF this is evaluated as chr = (getchar() != EOF) because the != operator has higher precendence than the assignment operator =, so you just need to add parentheses like this (chr = getchar()) != EOF Tip: Check...
Can't get to understand word counting in C [closed]
c,if-statement,boolean,state,getchar
Here is the code you posted with some comments: #include <stdio.h> #define IN 1 // in the code below, whenever you see IN, it's replaced by 1 #define OUT 0 // same as IN, but for 0 int main(void) { int nw, c, state; // nw is the number of...
Control-D ends getchar but not program, prog continues with garbage value in receiving variable?
Pressing CTRL+D doesn't terminate the program. Instead, it closes the stdin input stream. Most command-line utilities are designed to do something and then terminate after this happens. Contrast this with CTRL+C, which sends a kill signal to the program. Your code currently works by assigning the return value of getchar()...
Understanding getchar() in the character counting program in C
Adding some output will help you: #include <stdio.h> int main (void) { int c, nc = 0; while ((c = getchar ()) != EOF) { ++nc; printf ("Character read: %02x\n", (unsigned) c); } printf ("Number of chars: %d\n", nc); } The Windows console views the ^Z input as "send input...