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reading a single character in C


 
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# 1  
Old 01-24-2005
reading a single character in C

Can anyone help me?????



My problem is that i want to read only one charcter from keyboard. Each time my program waits to press enter or ^d. I don't want that. As soon as i press a charcter it should proceed to next statement in program without pressing enter or ^d.



please help me..........
# 2  
Old 01-24-2005
Try getchar(3).
# 3  
Old 01-24-2005
There is more to this than just getchar(). The terminal driver must be put into character mode and buffering must be disabled. See this post.
# 4  
Old 01-28-2005
#include <stdio.h>
/* character input */
int fgetc(FILE *stream);
int getc(FILE *stream);
int getchar(void);
int ungetc(int c, FILE *stream);

These read an unsigned char from the input stream where specified, or otherwise stdin. In each case, the next character is obtained from the input stream. It is treated as an unsigned char and converted to an int, which is the return value. On End of File, the constant EOF is returned, and the end-of-file indicator is set for the associated stream. On error, EOF is returned, and the error indicator is set for the associated stream. Successive calls will obtain characters sequentially. The functions, if implemented as macros, may evaluate their stream argument more than once, so do not use side effects here.

There is also the supporting ungetc routine, which is used to push back a character on to a stream, causing it to become the next character to be read. This is not an output operation and can never cause the external contents of a file to be changed. A fflush, fseek, or rewind operation on the stream between the pushback and the read will cause the pushback to be forgotten. Only one character of pushback is guaranteed, and attempts to pushback EOF are ignored. In every case, pushing back a number of characters then reading or discarding them leaves the file position indicator unchanged. The file position indicator is decremented by every successful call to ungetc for a binary stream, but unspecified for a text stream, or a binary stream which is positioned at the beginning of the file.

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