fgetc 是 file get char 的缩写,意思是从指定的文件中读取一个字符。fgetc() 的用法为: intfgetc(FILE *fp); fp 为文件指针。fgetc() 读取成功时返回读取到的字符,读取到文件末尾或读取失败时返回EOF。 EOF 是 end of file 的缩写,表示文件末尾,是在 stdio.h 中定义的宏,它的值是一个负数,往往是 -1。
#include <stdio.h> #include <stdlib.h> typedef struct { int id; char name[20]; float score; } Student; void writeBinaryFile(const char* filename) { FILE* file = fopen(filename, "wb"); if (!file) { perror("Failed to open file for writing"); return; } Student students[] = ...
__END_DECLS#define__SLBF 0x0001/* line buffered */#define__SNBF 0x0002/* unbuffered */#define__SRD 0x0004/* OK to read */#define__SWR 0x0008/* OK to write *//* RD and WR are never simultaneously asserted */#define__SRW 0x0010/* open for reading & writing */#define__SEOF...
fprintf(file,"Number: %d, Float: %.2f\n",42,3.14);// 3. 使用 fputs() 写入字符串(不包含格式化)fputs("This is another line.\n", file);// 4. 关闭文件fclose(file); printf("Data written successfully to example.txt\n");return0; ...
w(write):写 a(append):追加 t(text):文本文件 b(binary):二进制文件 +:读和写 以字符形式读写文件 以字符形式读写文件时,每次可以从文件中读取一个字符,或者向文件中写入一个字符。主要使用两个函数,分别是fgetc()和fputc()。 #include<stdio.h>intmain(){FILE*fp;char ch;//如果文件不存在,给出提...
float a = 2.3; // 单精度 double b = 4.5; // 双精度,当创建一个临时浮点数数值的时候,默认是double 1. 2. 为什么计算机中浮点数是这样表示的呢?相信大家都会有这个疑惑 讲解浮点数的构造 我们知道数值是计算机分成定点数和浮点数,浮点数的定义为:小数点的位置不固定,由指数,基数和阶层组成,用科学计数法...
However, the type library contained a reference to another type library that was not referenced with #import. This other .tlb file was not found by the compiler.Note that the compiler will not find type libraries in different directories if you use the /I (Additional Include Directories) ...
断言,是宏,而非函数。assert 宏的原型定义在<assert.h>(C)、<cassert>(C++)中,其作用是如果它的条件返回错误,则终止程序执行。可以通过定义NDEBUG来关闭 assert,但是需要在源代码的开头,include <assert.h>之前。 使用 代码语言:javascript 代码运行次数:0 ...
一般用于文件的内容比较的固定，比如，一行都是一个结构体的数据，下面从文件内容初始化结构体：测试范例data.txt的内容：#include<stdio.h>#include<string.h>structSTU{charname[100];intnum;floatscore;};intmain(){FILE*fp=fopen("data.txt","r");if(NULL==fp){perror("fopen err");return1;}charstr...
size_t fwrite ( const void * ptr, size_t size, size_t count, FILE * stream ); Write block of data to stream Writes an array of count elements, each one with a size of size bytes, from the block of memory pointed by ptr to the current position in the stream. The position indi...