Content · Web Development · PHP

PHP ftp_fput() Function: Usage and Examples

Uploads data from an opened local PHP stream to a remote.

1 views Published Oct 17, 2026 Updated Oct 17, 2026 admin

Uploads data from an opened local PHP stream to a remote file. This guide demonstrates its use in PHP code and explains when the result or side effect needs extra checks.

What It Does


Uploads data from an opened local PHP stream to a remote file.

Syntax and Parameters


The examples below show a real call to ftp_fput with suitable arguments. Read the function call in context: its connection, handle, input data or other prerequisites are created before use.

Requirements: FTP extension and a controlled test FTP/FTPS server; ftp_ssl_connect does not validate the server certificate.

Compatibility and security: Important: ftp_ssl_connect does not verify the server certificate; it is unsuitable alone for authenticating a remote FTPS server. Prefer a transport implementation with peer verification (or an approved SFTP client) for untrusted networks. FTP and SFTP are different protocols.

These examples are for an isolated development environment. Hostnames, credentials and remote paths must be replaced with your approved configuration.

Example 1: Core Behavior


Configure a test FTPS server and a dedicated low-privilege account before running this example.

<?php
$host = getenv('FTP_HOST'); $user = getenv('FTP_USER'); $pass = getenv('FTP_PASSWORD');
if (!$host || !$user || !$pass) { throw new RuntimeException('Configure FTP_HOST, FTP_USER and FTP_PASSWORD'); }
// ftp_ssl_connect does not verify the peer certificate; use only on a trusted test server.
$ftp = ftp_ssl_connect($host, 21, 8);
if (!$ftp || !ftp_login($ftp, $user, $pass)) { throw new RuntimeException('FTPS connection/login failed'); }
ftp_pasv($ftp, true);
$stream = fopen('php://temp', 'w+b');
if ($stream === false) throw new RuntimeException('Cannot open stream');
fwrite($stream, 'csv-row,42' . PHP_EOL); rewind($stream);
$ok = ftp_fput($ftp, '/incoming/report.csv', $stream, FTP_BINARY);
echo $ok ? "Operation succeeded" : "Operation failed";
fclose($stream);
ftp_close($ftp);

Observe the returned value or changed resource state. A successful function call can still require additional checks before a higher-level operation is considered successful.

Example 2: Alternative or Failure Case


Repeat with an account limited to the correct directory and check the returned status.

<?php
$host = getenv('FTP_HOST'); $user = getenv('FTP_USER'); $pass = getenv('FTP_PASSWORD');
if (!$host || !$user || !$pass) { throw new RuntimeException('Configure FTP_HOST, FTP_USER and FTP_PASSWORD'); }
// ftp_ssl_connect does not verify the peer certificate; use only on a trusted test server.
$ftp = ftp_ssl_connect($host, 21, 9);
if (!$ftp || !ftp_login($ftp, $user, $pass)) { throw new RuntimeException('FTPS connection/login failed'); }
ftp_pasv($ftp, true);
$stream = fopen('php://temp', 'w+b');
if ($stream === false) throw new RuntimeException('Cannot open stream');
fwrite($stream, 'csv-row,42' . PHP_EOL); rewind($stream);
$ok = ftp_fput($ftp, '/incoming/weekly.csv', $stream, FTP_BINARY);
echo $ok ? "Operation succeeded" : "Operation failed";
fclose($stream);
ftp_close($ftp);

Compare the different inputs, environment assumptions or result checks. Do not use a transport-level success value as proof that all business-level requirements were met.

Practical Example: Applying the Rule


A production workflow must also validate remote paths and handle errors without exposing credentials.

<?php
$host = getenv('FTP_HOST'); $user = getenv('FTP_USER'); $pass = getenv('FTP_PASSWORD');
if (!$host || !$user || !$pass) { throw new RuntimeException('Configure FTP_HOST, FTP_USER and FTP_PASSWORD'); }
// ftp_ssl_connect does not verify the peer certificate; use only on a trusted test server.
$ftp = ftp_ssl_connect($host, 21, 10);
if (!$ftp || !ftp_login($ftp, $user, $pass)) { throw new RuntimeException('FTPS connection/login failed'); }
ftp_pasv($ftp, true);
$stream = fopen('php://temp', 'w+b');
if ($stream === false) throw new RuntimeException('Cannot open stream');
fwrite($stream, 'csv-row,42' . PHP_EOL); rewind($stream);
$ok = ftp_fput($ftp, '/incoming/archive.csv', $stream, FTP_BINARY);
echo $ok ? "Operation succeeded" : "Operation failed";
fclose($stream);
ftp_close($ftp);

In an application, convert low-level failures into controlled responses and log only non-sensitive diagnostic context.

Important Behavior and Edge Cases


Rewind the stream to the intended position before uploading.

Check both authentication and operation results; FTP server capabilities and directory permissions vary. PHP ftp_ssl_connect does not verify TLS peer certificates, so the examples are limited to trusted test environments and are not a secure Internet-facing FTPS implementation.

Comparison with Related Functions or Patterns


ApproachWhen it differs
ftp_fputUploads data from an opened local PHP stream to a remote file.
Related API or patternftp_put uploads from a local filename instead.

Common Beginner Mistakes


MistakeCorrect approach
Writing or deleting an unchecked remote path with broad permissionsRewind the stream to the intended position before uploading.
Substituting a related API without checking its semanticsftp_put uploads from a local filename instead.

Key Takeaways


  • Uploads data from an opened local PHP stream to a remote file.
  • Rewind the stream to the intended position before uploading.
  • ftp_put uploads from a local filename instead.

Select this API or pattern based on its documented behavior and the trust boundaries in your own application, and test all external integrations against their actual deployments.

Share this resourceSend this page to someone who may find it useful.