Question

Really, I’m just generally confused on how to create a file in a subdirectory of the current working directory, but especially if it’s hidden.

Say char* backup contains the name of the file we’re creating with an open() call.

Say there’s a hidden folder which already exists called .mybackup.

How do I create the file inside of .mybackup? Hopefully without chdir’ing twice.

Where I’m at so far:

int filewrite;
filewrite = open(backup, O_CREAT | O_RDWR, 0644);

Answer 1

Prepend the filename with the directory you’d like it to be placed in. Or, chdiring twice would also be acceptable.

char* backup = "backup.sql";   // Assuming this comes from somewhere else (not constant)

const char* targetDir = ".mybackup/";   // (No leading slash)

// Allocate a buffer for the filename (remembering +1 for null-terminator!)
char* path = (char*)malloc(strlen(targetDir) + strlen(backup) + 1);

strcpy(path, targetDir);   // Copy in the target directory part
strcat(path, backup);      // Copy in the filename part


filewrite = open(path, O_CREAT | O_RDWR, 0644);  // Open the file

free(path);   // Free the buffer