Objective-C

Clear the FTP Directory Listing Cache

Demonstrates the Chilkat Ftp2.ClearDirCache method, which clears the cached listing for the current remote directory. It takes no arguments; the next indexed-listing call fetches a fresh listing from the server.

Background: The index-based directory API caches the listing the first time you read it, so repeated accessor calls avoid extra round trips. The trade-off is staleness: if the directory changes — files added or removed, whether by your own operations or another process — the cache still reflects the old state. ClearDirCache discards it so the next GetDirCount queries the server again.

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Objective-C

#import <CkoFtp2.h>

BOOL success = NO;

//  Demonstrates the Ftp2.ClearDirCache method, which clears the cached listing for the current
//  remote directory.  It takes no arguments and is a void method.

CkoFtp2 *ftp = [[CkoFtp2 alloc] init];

ftp.Hostname = @"ftp.example.com";
ftp.Username = @"myFtpLogin";

//  Normally you would not hard-code the password in source.  You should instead obtain it
//  from an interactive prompt, environment variable, or a secrets vault.
ftp.Password = @"myPassword";

success = [ftp Connect];
if (success == NO) {
    NSLog(@"%@",ftp.LastErrorText);
    return;
}

success = [ftp ChangeRemoteDir: @"public_html"];
if (success == NO) {
    NSLog(@"%@",ftp.LastErrorText);
    return;
}

//  The first GetDirCount caches the listing.
int n = [[ftp GetDirCount] intValue];
NSLog(@"%@%d",@"Entries: ",n);

//  ... the remote directory changes (files added or removed by another process) ...

//  Discard the cache so the next listing call fetches fresh data from the server.
[ftp ClearDirCache];

n = [[ftp GetDirCount] intValue];
NSLog(@"%@%d",@"Entries after refresh: ",n);

success = [ftp Disconnect];
if (success == NO) {
    NSLog(@"%@",ftp.LastErrorText);
    return;
}