c语言 字符串的使用

1、http://bbs.csdn.net/topics/330194493

char *encode=getenv("LANG");
    char *search=".";
    //查找字符串
    int pos=strcspn(encode,search);
    char str[1024];
    //求子字符串
    strncpy(str,encode+pos+strlen(search),strlen(encode)-pos);
    
    printf("%s\n",str);

 

int append_to_file_by_c(char *filename,char* content)
{
	FILE *file;
	file=fopen(filename,"a");
	if(file==NULL)
	{
		return -1;
	}
	//fseek(file, 0L, SEEK_END);
	fwrite(content,strlen(content),1,file);
	fclose(file);
	return 0;
}
int main(int argc, char **argv)
{
	char content[1024]={0};
	char time_str[1024]={0};
	time_t rawtime; 
	struct tm * timeinfo; 
	time ( &rawtime ); 
	timeinfo =localtime(&rawtime); 
	//printf("The current date/time is: %s", asctime (timeinfo)); 
	sprintf(time_str,"%4d-%02d-%02d %02d:%02d:%02d ",1900+timeinfo->tm_year, 1+timeinfo->tm_mon,
	timeinfo->tm_mday,timeinfo->tm_hour,timeinfo->tm_min,timeinfo->tm_sec);
	//printf("%s\n",time_str);
	strcat_s(content,time_str);
	for(int i=0;i<argc;i++)
	{
		strcat_s(content,argv[i]);
		strcat_s(content," ");
	}
	strcat_s(content,"\n");
	append_to_file_by_c("adb_log.txt",content);