C언어에서 문자열 입/출력 예
#include <stdio.h>
#include <string.h>
/*
키보드(표준입력, stdin스트림)로부터 문자열을 입력하는 함수들
gets() : The gets() function reads characters from stdin and loads them into str, until a newline or EOF is reached.
The newline character is translated into a null termination.
The return value of gets() is the read-in string, or NULL if there is an error.
Note that gets() does not perform bounds checking, and thus risks overrunning str.
For a similar (and safer) function that includes bounds checking, see fgets().
fgets() : The function fgets() reads up to num - 1 characters from the given file stream and dumps them into str.
The string that fgets() produces is always NULL- terminated.
fgets() will stop when it reaches the end of a line, in which case str will contain that newline character.
Otherwise, fgets() will stop when it reaches num - 1 characters or encounters the EOF character.
fgets() returns str on success, and NULL on an error.
scanf() : 공백문자로 구분된 한개의 문자열을 가져온다
fscanf() :
puts() :
fputs() :
printf() :
fprintf() :
*/
int main(int argc, char * argv[]) {
char dest[20], temp[2];
int count = 0;
puts("문자열을 입력하고 엔터를 치세요. 종료(x)");
while(1) {
printf("문자열 입력:");
gets(dest);
if(strcmp(dest,"x")==0) break;
printf("\n입력된 문자열="); puts(dest);
fflush(stdin);
}
printf("gets()끝--------------------scanf()시작\n");
fflush(stdin);
while(1) {
printf("문자열 입력:");
count = scanf("%s", dest);
if(strcmp(dest,"x")==0) break;
printf("\n입력된 문자열=%s\n",dest);
fflush(stdin);
}
printf("scanf()끝--------------------fscanf()시작\n");
fflush(stdin);
while(1) {
printf("문자열 입력:");
count = fscanf(stdin, "%s", dest);
if(strcmp(dest,"x")==0) break;
fprintf(stdout, "\n입력된 문자열=%s\n",dest);
fflush(stdin);
}
printf("fscanf()끝--------------------fgets()시작\n");
fflush(stdin);
/* fgets()함수는 한 라인을 읽을 때 개행문자도 포함하여 읽어온다
* 그러므로 위와같은 같은 방법으로는 루프를 종료할 수 없다 */
while(1) {
printf("문자열 입력:");
fgets(temp, sizeof(temp), stdin); //개행문자('\n') 포함됨
strncpy(dest,temp,strlen(temp)-1); //개행문자 제검됨
dest[strlen(temp)-1] = '\0'; //'\0' 추가함
if(strcmp(dest,"x")==0) break;
printf("%s, len=%d\n", dest, strlen(dest));
printf("\n입력된 문자열="); fputs(dest,stdout);
fflush(stdin);
}
}