AIX:struct dirent d_type

AIX:struct dirent d_type

今天做一个小功能，实现起来时需要判断一个目录下各个目录项对应的类型：

可能是普通文件类型；

可能是目录类型；

可能是SOCKET类型…

#include <stdio.h>#include <stdlib.h>#include <unistd.h>#include <sys/types.h>#include <dirent.h>int main(){        DIR *dir;        struct dirent *item;        dir = opendir("/home/filter");        while ((item = readdir(dir)) != NULL)        {                if (item->d_type & DT_DIR)                {                        printf("%s\n", item->d_name);                }        }        closedir(dir);        return 0;}

这段代码在Linux上编译运行没啥问题，但是在AIX环境下就编译不通过。

Linux下：

[filter@localhost ~]$ uname -aLinux localhost.localdomain 2.6.18-371.el5 #1 SMP Thu Sep 5 21:21:44 EDT 2013 x86_64 x86_64 x86_64 GNU/Linux[filter@localhost ~]$ gcc -o main main.c[filter@localhost ~]$ ./main...abc.mozilla.ssh

AIX下：

ismp@aix68113:/home/ismp>uname -a       AIX aix68113 1 6 00F7CAA94C00ismp@aix68113:/home/ismp>cc -o main main.c"main.c", line 16.27: 1506-022 (S) "d_type" is not a member of "struct dirent"."main.c", line 16.36: 1506-045 (S) Undeclared identifier DT_DIR.

没有编译通过。

查看对应的头文件：

Linux下：

/usr/include/dirent.h/usr/include/bits/dirent.hstruct dirent  {#ifndef __USE_FILE_OFFSET64    __ino_t d_ino;    __off_t d_off;#else    __ino64_t d_ino;    __off64_t d_off;#endif    unsigned short int d_reclen;    unsigned char d_type;    char d_name[256];           /* We must not include limits.h! */  };

AIX下：

/usr/include/dirent.h/usr/include/sys/dir.h#define _D_NAME_MAX 255struct  dirent {        __ulong64_t     d_offset;       /* real off after this entry */        ino_t           d_ino;          /* inode number of entry */        ushort_t        d_reclen;       /* length of this record */        ushort_t        d_namlen;       /* length of string in d_name */        char            d_name[_D_NAME_MAX+1];  /* name must be no longer than this */                                        /* redefine w/#define when name decided */};

AIX下man手册：

man dirent.h       ulong_t d_offset;                /* actual offset of this entry */       ino_t           d_ino;           /* inode number of entry */       ushort_t        d_reclen;        /* length of this entry */       ushort_t        d_namlen;        /* length of string in d_name */       char d_name[_D_NAME_MAX+1];      /* name of entry (filename) */

可见，在AIX下，struct dirent没有d_type这个字段。

附上Linux下d_type值表：

/usr/include/dirent.h/* File types for `d_type'.  */enum  {    DT_UNKNOWN = 0,# define DT_UNKNOWN     DT_UNKNOWN    DT_FIFO = 1,# define DT_FIFO        DT_FIFO    DT_CHR = 2,# define DT_CHR         DT_CHR    DT_DIR = 4,# define DT_DIR         DT_DIR    DT_BLK = 6,# define DT_BLK         DT_BLK    DT_REG = 8,# define DT_REG         DT_REG    DT_LNK = 10,# define DT_LNK         DT_LNK    DT_SOCK = 12,# define DT_SOCK        DT_SOCK    DT_WHT = 14# define DT_WHT         DT_WHT  };

其他说明：

This member is a BSD extension. The symbol _DIRENT_HAVE_D_TYPE is defined if this member is available. On systems where it is used, it corresponds to the file type bits in the st_mode member of struct stat. If the value cannot be determined the member value is DT_UNKNOWN.来源：http://www.gnu.org/software/libc/manual/html_node/Directory-Entries.html