Problem with strcat()

[souza]

What's wrong with my functions ? I need to check if the files found are dirs! but when a use strcat() for sum de localdir and the name.... puff !! segment fault !!! thanks

void scan (char *localDir) {
    struct dirent **namelist;
    int n;
    n = scandir(localDir, &namelist, 0, alphasort);
    if (n < 0)
        perror("scandir");
    else {
        while(n--) {
	    char *filename = strcat(localDir, namelist[n]->d_name);
	    if (isDir(filename) {
                    printf("%s \n", filename);
	    }
            free(namelist[n]);
        }
        free(namelist);
    }

}

[Salem]

Say you have
.
..
foo.dat
bar.txt

> char *filename = strcat(localDir, namelist[n]->d_name);
localDir is going to end up being one long long string of
...foo.datbar.txt

Are you sure it's
a) what you wanted to do
b) long enough
c) initialised with a suitable \0 ending string to begin with.

[souza]

Salem,

I need to check if the found files are a directories.. is simple. but I am never coder C before.
I can make the software print the file names on the screen... but, I need use, something like strcat(), for union DIRNAME (where scandir() search files) and the FILENAMES (namelist[n]->d_name). So, I can check with:
isDir(filename) !
thanks for your help

[Salem]

What's wrong with
isDir(namelist[n]->d_name)

[souza]

if I am not on the current dir ? ...namelist[n]->d_name is just the file name

[Salem]

So you really want to create
mydir/.
mydir/..
mydir/foo.dat
mydir/bar.txt

Perhaps something along these lines, inside the loop
char temp[size]; // you pick a size
strcpy( temp, dir );
strcat( temp, file );

[souza]

thats it !! thanks a lot Salem.
I dont know why, but strcpy() save my code !

cya