How to Wait for Output Patterns

Overview

Synchronize your recording with terminal output by waiting for specific patterns or shell prompts.

Basic Wait Command

Wait

Without arguments, Wait looks for the default shell prompt pattern (configured per shell).

Example:

Type "ls"
Enter
Wait       # Waits for prompt to reappear

Waiting for Patterns

To wait for specific output, use a regex pattern in forward slashes:

Wait /pattern/

Common patterns:

Wait /Complete/           # Literal word
Wait /Build succeeded/    # Phrase with space
Wait /\d+ tests passed/   # Number + text (matches "5 tests passed", "100 tests passed")

Examples:

# Wait for build completion
Exec "dotnet build"
Wait /Build succeeded/
  
# Wait for server startup
Exec "npm start"
Wait /Server listening on port/
  
# Wait for test results
Exec "pytest"
Wait /\d+ passed/

Wait Scopes

Wait has three scope modes that control where it searches for patterns:

Wait+Buffer (Default)

Searches in a persistent buffer that accumulates output across multiple Wait commands.

Wait+Buffer /pattern/
# or just
Wait /pattern/            # Buffer is default

Use for fast-scrolling output or multi-line patterns:

Exec "npm install"
Wait+Buffer /added.*packages/    # Catches message even if it scrolls fast

Wait+Line

Searches only the current terminal line.

Wait+Line /pattern/

Use for prompt detection or single-line status messages:

Type "echo 'Done'"
Enter
Wait+Line /Done/       # Only check current line

Wait+Screen

Searches the entire visible terminal screen.

Wait+Screen /pattern/

Use for TUI applications or multi-line visible output:

Exec "htop"
Wait+Screen /Load average/    # Find in visible screen content

Custom Timeouts

Override the default 15-second timeout:

Wait@30s /pattern/

When to Use Custom Timeouts

Long-running operations:

Exec "docker build -t myapp ."
Wait@5m /Successfully built/     # Build can take minutes

Quick operations (shorter timeout):

Type "echo hi"
Enter
Wait@2s                          # Should finish quickly

Combining Scope and Timeout

Wait+<scope>@<duration> /pattern/

Examples:

Wait+Buffer@30s /Complete/
Wait+Line@5s />\s*$/
Wait+Screen@10s /Status: OK/

Examples

Wait for build completion:

Exec "cargo build --release"
Wait@3m /Finished release/        # Rust builds can be slow

Wait for server startup:

Exec "python -m http.server 8000"
Wait /Serving HTTP on/            # Wait for server ready message

Chain multiple waits:

Exec "npm test"
Wait /Tests started/              # Wait for tests to begin
Sleep 2s                          # Pause to show progress
Wait /Tests completed/            # Wait for completion

Troubleshooting

Pattern Not Matching

Problem: Wait times out even though output appeared.

Solutions:

  1. Check your regex:

    # Bad: Missing escape
Wait /Build succeeded./       # '.' matches any character
  
# Good: Escaped correctly
Wait /Build succeeded\./      # Literal period

  2. Use broader scope:

    Wait+Buffer /pattern/         # Instead of Wait+Line

  3. Check case sensitivity:

    # Regex is case-sensitive by default
Wait /success/                # Won't match "Success"
Wait /[Ss]uccess/             # Matches both

Timeout Too Short

Problem: Command takes longer than expected.

Solution:

Set WaitTimeout 30s              # Increase default
# or
Wait@60s /pattern/               # Override for specific Wait

Output Scrolls Too Fast

Problem: Pattern appears but Wait misses it (happens with Wait+Line).

Solution:

Wait+Buffer /pattern/            # Use Buffer scope (default)

Best Practices

  • Use specific patterns - Wait /Build done in \d+ms/ is better than Wait /done/ which might match unrelated output
  • Match actual output format - Check your actual output first, then write the pattern
  • Combine with Exec for real output - More reliable than Type+Enter since Exec captures actual command output
  • Set appropriate timeouts - Use @5s for fast operations, @5m for slow builds
  • Use default Wait for prompts - Just Wait with no pattern waits for the shell prompt to return
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