Problem Statement

sudo apt update
sudo apt upgrade

But Visual Studio Code (Visual Studio Code) remains outdated.

sudo apt install --only-upgrade code

it updates successfully.

This behavior is not accidental. It is a consequence of how APT resolves dependencies under different upgrade strategies.

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Key Concept: APT Upgrade Policies

APT provides multiple upgrade strategies with different levels of aggressiveness:

Command	Behavior
apt upgrade	Upgrades packages without installing or removing dependencies
apt full-upgrade	Allows installing/removing dependencies to complete upgrades
apt install --only-upgrade <pkg>	Forces upgrade of a specific package, allowing dependency resolution

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What Happened in This Case

During the upgrade attempt, APT reported:

The following NEW packages will be installed:
  socat

This is the critical detail.

The new version of VS Code introduced a new dependency: socat.

Under apt upgrade, APT refused to proceed because:

• It would require installing a new package (socat)
• This violates the conservative policy of apt upgrade

As a result:

• VS Code remained at version 1.114.0
• No upgrade occurred

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Why --only-upgrade Worked

When you executed:

sudo apt install --only-upgrade code

APT switched to a targeted resolution strategy:

• The goal became: upgrade code
• APT was allowed to:
  • Install required dependencies (socat)
  • Complete the upgrade

Result:

code 1.114.0 → 1.117.0

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Dependency Evolution in Packages

This situation is common when:

• A package introduces new runtime features
• New dependencies are added in newer versions

In Debian-based systems (like Ubuntu), package metadata defines:

• Depends
• Recommends
• Suggests

If a new version modifies Depends, upgrading may require additional packages.

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Correct Upgrade Strategies

Safe Global Upgrade

sudo apt upgrade

Use when you want minimal system changes.

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Complete System Upgrade

sudo apt full-upgrade

Use when:

• You want all packages updated
• You accept dependency changes

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Targeted Package Upgrade

sudo apt install --only-upgrade code

Use when:

• A specific package is blocked
• You want precise control

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Verification

After upgrade:

code --version