S_ISDIR returning different value for directory [closed] - c

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I'm currently trying to do some kind of recursive find where I need to distinguish regular files with directory.
I made a loop to check with S_ISDIR if a given file is a directory but when applied to /home, I don't get the expected result.
I only have a pome directory in /home so expected result would be :
/home/.
/home/..
/home/pome
but it doesn't detect pome as a directory, S_ISDIR() returns 0 for pome and 1 for . and ..
Code :
DIR * dir = opendir("/home");
if(dir==NULL){
puts("Unknown directory");
return 1;
}
char path[SIZE_PATH];
memset(path,'\0',sizeof(path));
strcpy(path,"/home");
struct dirent * trucdir;
char filename[SIZE_PATH];
memset(filename,'\0',sizeof(filename));
struct stat * filestat=malloc(sizeof(struct stat));
while((trucdir=readdir(dir))!=NULL){
memset(filename,'\0',sizeof(filename));
strcpy(filename,trucdir->d_name);
stat(filename,filestat);
if(S_ISDIR(filestat->st_mode)!=0){
puts(filename);
}
}
Isn't S_ISDIR supposed to return a non-zero value if the file is a directory ?

Answer 1

You have to check, that your stat()-call actually succeeds by checking its return value. In your case, the call to stat is:
stat("pome", filestat);
but your current working directory (cwd) is not /home!
Hence, the call to stat fails with -1 and errno ENOENT and the IS_DIR-macro is meaningless. The stat-calls to . and .. of course succeed, since they are present in all directories (although other information like inode number etc. doesn't match then)
You have to make sure that you either provide the full path in filename (i.e. /home/pome) or you set the cwd to /home before (with chdir("/home");); this should solve your issue!