#include <iconv.h> #include <stdlib.h> #include <stdio.h> #include <unistd.h> #include <fcntl.h> #include <string.h> #include <sys/stat.h> int code_convert(char *from_charset, char *to_charset, char *inbuf, size_t inlen, char *outbuf, size_t outlen) { iconv_t cd; char **pin = &inbuf; char **pout = &outbuf; cd = iconv_open(to_charset, from_charset); if (cd == 0) return -1; memset(outbuf, 0, outlen); if (iconv(cd, pin, &inlen, pout, &outlen) == -1) return -1; iconv_close(cd); *pout = '\0'; return 0; } int u2g(char *inbuf, size_t inlen, char *outbuf, size_t outlen) { return code_convert("utf-8", "gb2312", inbuf, inlen, outbuf, outlen); } int g2u(char *inbuf, size_t inlen, char *outbuf, size_t outlen) { return code_convert("gb2312", "utf-8", inbuf, inlen, outbuf, outlen); } int main(void) { char *s = "中国"; int fd = open("test.txt", O_RDWR|O_CREAT, S_IRUSR | S_IWUSR); char buf[10]; u2g(s, strlen(s), buf, sizeof(buf)); write(fd, buf, strlen(buf)); close(fd); fd = open("test.txt2", O_RDWR|O_CREAT, S_IRUSR | S_IWUSR); char buf2[10]; g2u(buf, strlen(buf), buf2, sizeof(buf2)); write(fd, buf2, strlen(buf2)); close(fd); return 1; }
上面是使用iconv函数。
方式二: 使用如下两个函数
mbstowcs将多字节编码转换为宽字节编码
wcstombs将宽字节编码转换为多字节编码
注意, 需要系统编码的支持, 可以通过locale -a 查看系统支持的。若不支持zh_CN.gbk, 需要安装,例如,在ubuntu上的安装步骤如下:
编辑
$sudo vi /var/lib/locales/supported.d/zh-hans更新成
zh_CN.UTF-8 UTF-8 zh_SG.UTF-8 UTF-8 zh_CN.GBK GBK zh_CN.GB18030 GB18030
// 更新 $ sudo locale-gen // 查看 $ locale -a C POSIX zh_CN.gb18030 zh_CN.gbk zh_CN.utf8 zh_SG.utf8
#include <stdlib.h> #include <stdio.h> #include <string.h> #include <unistd.h> #include <fcntl.h> #include <sys/stat.h> #include <locale.h> /** * DESCRIPTION: 实现由utf8编码到gbk编码的转换 * * Input: gbkStr,转换后的字符串; srcStr,待转换的字符串; maxGbkStrlen, gbkStr的最 大长度 * Output: gbkStr * Returns: -1,fail;>0,success * */ int utf82gbk(char *gbkStr, const char *srcStr, int maxGbkStrlen) { if (NULL == srcStr) { printf("Bad Parameter\n"); return -1; } //首先先将utf8编码转换为unicode编码 if (NULL == setlocale(LC_ALL, "zh_CN.utf8")) //设置转换为unicode前的码,当前为utf8编码 { printf("Bad Parameter\n"); return -1; } int unicodeLen = mbstowcs(NULL, srcStr, 0); //计算转换后的长度 if (unicodeLen <= 0) { printf("Can not Transfer!!!\n"); return -1; } wchar_t *unicodeStr = (wchar_t *) calloc(sizeof(wchar_t), unicodeLen + 1); mbstowcs(unicodeStr, srcStr, strlen(srcStr)); //将utf8转换为unicode //将unicode编码转换为gbk编码 if (NULL == setlocale(LC_ALL, "zh_CN.gbk")) //设置unicode转换后的码,当前为gbk { printf("Bad Parameter\n"); return -1; } int gbkLen = wcstombs(NULL, unicodeStr, 0); //计算转换后的长度 if (gbkLen <= 0) { printf("Can not Transfer!!!\n"); return -1; } else if (gbkLen >= maxGbkStrlen) //判断空间是否足够 { printf("Dst Str memory not enough\n"); return -1; } wcstombs(gbkStr, unicodeStr, gbkLen); gbkStr[gbkLen] = 0; //添加结束符 free(unicodeStr); return gbkLen; } int main(void) { char *s = "中国"; int fd = open("test.txt", O_RDWR | O_CREAT, S_IRUSR | S_IWUSR); char buf[10]; utf82gbk(buf, s, sizeof(buf)); write(fd, buf, strlen(buf)); close(fd); return 1; }