In the past, when parsing regular files, I either used regular expressions, or stupidly wrote my own program to parse regular files. Today I suddenly discovered that there is a ready-made function in the c library function that can parse regular files, which is the fscanf() function.
##fscanf is located in the header fileC language video tutorial)
fscanf() function (a bit like a regular expression): Function: Perform formatted input from a stream, fscanf ends when it encounters a space or a newline. Note that it also ends when it encounters a space. Usage: int fscanf(FILE *stream, char *format,[argument...]);int fscanf(file pointer, format string, input list);Return value: integer, returns the number of parameters read successfully, and returns EOF(-1) on failure.
Example 1:
#include <stdlib.h> #include <stdio.h> int main(void) { int i; printf("Input an integer:"); /*从标准输入中读取一个整数*/ if(fscanf(stdin, "%d",&i)) printf("The integer read was:%d\n", i); else { fprintf(stderr, "Error reading an integer from stdin.\n"); exit(1); } return 0; } 返回EOF如果读取到文件结尾。
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