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Run Applications

Execute applications inside your FlatImage container.

One-Time Execution

Use fim-exec to run commands without entering the container:

# Run Firefox once
./app.flatimage fim-exec firefox

# Run with arguments
./app.flatimage fim-exec firefox https://example.com

# Run shell commands
./app.flatimage fim-exec sh -c 'ls -la /usr/bin | grep python'

Set Default Boot Command

Configure what runs when you execute the FlatImage without arguments.

Set the Boot Command

# Set Firefox as default
./app.flatimage fim-boot set firefox

# Now this launches Firefox directly
./app.flatimage

With Pre-configured Arguments

# Always start Firefox in private mode
./app.flatimage fim-boot set firefox --private-window

# Launch with the pre-configured argument
./app.flatimage https://example.com
# Equivalent to: firefox --private-window https://example.com

View Current Boot Command

./app.flatimage fim-boot show

Output: 

{
  "args": ["--private-window"],
  "program": "firefox"
}

Clear Boot Command

Revert to default bash shell:

./app.flatimage fim-boot clear

Complete Example

Create a portable application launcher:

# Download and setup
wget -O alpine.flatimage https://github.com/flatimage/flatimage/releases/latest/download/alpine-x86_64.flatimage
chmod +x alpine.flatimage

# Configure permissions
./alpine.flatimage fim-perms add network,xorg,wayland,audio

# Install Firefox
./alpine.flatimage fim-root apk add firefox font-noto

# Set as boot command
./alpine.flatimage fim-boot set firefox

# Commit everything
./alpine.flatimage fim-layer commit binary

# Rename for clarity
mv alpine.flatimage firefox.flatimage

# Now it works like a native executable
./firefox.flatimage
./firefox.flatimage https://example.com

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