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一、Linux 创建目录函数mkdir的mode设置问题

函数原型：

#include <sys/stat.h>

int mkdir(const char *path, mode_t mode);

参数：

path是目录名

mode是目录权限

返回值：

返回0 表示成功， 返回 -1表示错误，并且会设置errno值。

mode模式位：

S_IRUSR：用户读权限

S_IWUSR：用户写权限

S_IRGRP：用户组读权限

S_IWGRP：用户组写权限

S_IROTH：其他组都权限

S_IWOTH：其他组写权限

mode 表示新目录的权限，可以取以下值：

S_IRUSR

S_IREAD

S_IWUSR

S_IWRITE

S_IXUSR

S_IEXEC

S_IRWXU

This is equivalent to (S_IRUSR | S_IWUSR | S_IXUSR).

S_IRGRP

Read permission bit for the group owner of the file. Usually 040.

S_IWGRP

Write permission bit for the group owner of the file. Usually 020.

S_IXGRP

Execute or search permission bit for the group owner of the file. Usually 010.

S_IRWXG

This is equivalent to (S_IRGRP | S_IWGRP | S_IXGRP).

S_IROTH

Read permission bit for other users. Usually 04.

S_IWOTH

Write permission bit for other users. Usually 02.

S_IXOTH

Execute or search permission bit for other users. Usually 01.

S_IRWXO

This is equivalent to (S_IROTH | S_IWOTH | S_IXOTH).

S_ISUID

This is the set-user-ID on execute bit, usually 04000. See How Change Persona.

S_ISGID

This is the set-group-ID on execute bit, usually 02000. See How Change Persona.

S_ISVTX

This is the sticky bit, usually 01000.

例子：

#include <sys/types.h> #include <sys/stat.h>

int status;

status = mkdir(“/home/newdir”, S_IRWXU | S_IRWXG | S_IROTH | S_IXOTH);

这样就创建了一个newdir目录，权限通过ls -al 查看为

drwxr-xr-x

跟用linux命令mkdir创建的目录权限位一致。

二、. linux下C语言创建多级目录

int CreateDir(const char *sPathName)
{
	char DirName[256];
	strcpy(DirName, sPathName);
	int i,len = strlen(DirName);
	if(DirName[len-1]!='/')
	strcat(DirName, "/");

	len = strlen(DirName);

	for(i=1; i<len; i++)
	{
		if(DirName[i]=='/')
		{
			DirName[i] = 0;
			if( access(DirName, NULL)!=0 )
			{
				if(mkdir(DirName, 0755)==-1)
				{
				perror("mkdir error");
				return -1;
				}
			}
			DirName[i] = '/';
		}
	}

	return 0;	
}

三、linux 编程：创建一个线程，监视某个目录，一旦目录里出现新的文件，就将文件转移到指定的目录里去。

#define SRCPATH "srcpath/"
#define DSTPATH "dstpath/"

int movefile()
{
	DIR *dir;
	struct dirent *dt;
	FILE *fp1,*fp2;
	char filename1[256],filename2[256];
	char buf[1024];
	int readsize,writesize;

	if((dir = opendir(SRCPATH)) == NULL)
	{
		printf("opendir %s error\n",SRCPATH);
		return -1;
	}
	memset(filename1,0,sizeof(filename1));
	strcpy(filename1,SRCPATH);
	memset(filename2,0,sizeof(filename2));
	strcpy(filename2,DSTPATH);
	while(1)
	{
		while((dt = readdir(dir)) != NULL)
		{
			if(strcmp(dt->d_name,".")==0||strcmp(dt->d_name,"..")==0)
			{
			continue;
			}
			//如果这个目录里 还有目录，可以在这加判断
			//这里假设初始为空目录
			strcat(filename1,dt->d_name);
			strcat(filename2,dt->d_name);
			//如果进程资源较少可以直接用linux系统命令

			fp1 = fopen(filename1,"rb");
			if(fp1==NULL)
			{
				printf("open %s failed /n",filename1);
				return -1;
			}

			fp2 = fopen(filename2,"wb");
			if(fp2==NULL)
			{
				printf("open %s failed /n",filename2);
				fclose(fp1);
				return -1;
			}

			while((readsize = fread(buf,sizeof(buf),1,fp1))>0)
			{
				//total += readsize;
				memset(buf,0,sizeof(buf));
				writesize = fwrite(buf,sizeof(buf),1,fp2);
				if(writesize!==readsize)
				{
					printf("write error");
					return -2;
					fclose(fp1);
					fclose(fp2);
				}
			}
			fclose(fp1);
			fclose(fp2);
			rmdir(filename2);
		}
	}
}

int main(int argc,char **argv)
{
pthread_t id1;
int ret;
ret = pthread_create(&id1, NULL, (void*)movefile, NULL);
return ret;
}