Perforce Basics

Overview

Perforce (P4) is a centralized version control system optimized for large codebases and binary assets. This skill covers essential daily operations.

When to Use

• Syncing latest changes
• Editing files for modification
• Adding new files
• Deleting files
• Submitting changes
• Reverting unwanted changes

Core Concepts

File States

Revision Specifiers

# Specific revision number
file.txt#3

# Head revision (latest)
file.txt#head

# Changelist number
file.txt@12345

# Label
file.txt@release_1.0

# Date/time
file.txt@2024/01/15
file.txt@2024/01/15:14:30:00

# Revision range
file.txt#2,#5
file.txt@10000,@12000

Sync Operations

Basic Sync

# Sync entire workspace to head
p4 sync

# Sync specific path
p4 sync //depot/project/...

# Sync specific file
p4 sync //depot/project/file.txt

# Sync to specific revision
p4 sync //depot/project/...#head
p4 sync //depot/project/...@12345

# Sync to specific changelist
p4 sync @12345

Sync Options

# Preview sync (don't actually sync)
p4 sync -n //depot/project/...

# Force sync (re-download even if up to date)
p4 sync -f //depot/project/...

# Parallel sync (faster for many files)
p4 sync --parallel=threads=4 //depot/project/...

# Safe sync (don't clobber writable files)
p4 sync -s //depot/project/...

# Sync and show affected files
p4 sync //depot/project/... 2>&1 | head -50

Selective Sync

# Sync only specific file types
p4 sync //depot/project/....cs
p4 sync //depot/project/....prefab

# Sync excluding paths (use workspace view instead)
# Or sync specific subdirectories
p4 sync //depot/project/Assets/Scripts/...

Edit Operations

Opening Files for Edit

# Edit single file
p4 edit file.txt

# Edit multiple files
p4 edit *.cs

# Edit files in directory
p4 edit Assets/Scripts/...

# Edit with specific changelist
p4 edit -c 12345 file.txt

# Edit to default changelist
p4 edit -c default file.txt

Check Edit Status

# See files open for edit
p4 opened

# See files open in specific changelist
p4 opened -c 12345

# See files open by all users
p4 opened -a //depot/project/...

# See who has file open
p4 opened -a //depot/project/file.txt

Add Operations

Adding New Files

# Add single file
p4 add newfile.txt

# Add multiple files
p4 add *.cs

# Add files recursively
p4 add Assets/NewFeature/...

# Add to specific changelist
p4 add -c 12345 newfile.txt

# Add with specific file type
p4 add -t binary+l largefile.bin
p4 add -t text+x script.sh

File Types

# Common file types
text        # Text file, diff/merge enabled
binary      # Binary file, no diff/merge
unicode     # Unicode text
symlink     # Symbolic link

# Modifiers
+l          # Exclusive lock (only one user can edit)
+w          # Always writable on client
+x          # Executable bit
+S          # Only head revision stored (saves space)
+F          # Check for RCS keywords

# Examples
p4 add -t binary+l Assets/Textures/hero.psd    # Locked binary
p4 add -t text Assets/Scripts/Player.cs         # Text file

Delete Operations

Deleting Files

# Delete single file
p4 delete file.txt

# Delete multiple files
p4 delete *.bak

# Delete in specific changelist
p4 delete -c 12345 file.txt

# Delete files matching pattern
p4 delete //depot/project/....tmp

Handling Deleted Files

# See deleted files in depot
p4 files //depot/project/...@head | grep "delete change"

# Recover deleted file (sync old revision, then add)
p4 sync //depot/project/file.txt#head-1
p4 add file.txt

# Or use obliterate (admin only) to permanently remove

Revert Operations

Reverting Changes

# Revert single file
p4 revert file.txt

# Revert all files in changelist
p4 revert -c 12345 //...

# Revert all open files
p4 revert //...

# Revert unchanged files only
p4 revert -a //...

# Revert with preview
p4 revert -n //...

Revert to Specific Revision

# Sync to old revision (makes file read-only)
p4 sync //depot/project/file.txt#3

# To actually revert content and submit:
p4 sync //depot/project/file.txt#head
p4 edit file.txt
p4 sync -f //depot/project/file.txt#3
p4 resolve -ay file.txt
# Now submit

Submit Operations

Submitting Changes

# Submit default changelist (opens editor for description)
p4 submit

# Submit specific changelist
p4 submit -c 12345

# Submit with description
p4 submit -d "Fix player movement bug"

# Submit specific files from default changelist
p4 submit file.txt

# Submit and reopen files for further editing
p4 submit -r -c 12345

Pre-Submit Checks

# Check what will be submitted
p4 opened -c default

# Check for conflicts before submit
p4 sync
p4 resolve

# Verify files are correct
p4 diff -se //...  # Files that differ from depot

# Check changelist description
p4 change -o 12345

Status Commands

Workspace Status

# Files open for edit/add/delete
p4 opened

# Files that need sync
p4 sync -n //...

# Files modified but not opened (reconcile needed)
p4 status

# Reconcile local changes with depot
p4 reconcile //...

Depot Status

# List files in depot
p4 files //depot/project/...

# List files with specific pattern
p4 files //depot/project/....cs

# Get file info
p4 fstat //depot/project/file.txt

# Detailed file info
p4 fstat -Ol //depot/project/file.txt

Reconcile Operations

Finding Untracked Changes

# Find all local changes not in Perforce
p4 reconcile //...

# Preview reconcile
p4 reconcile -n //...

# Reconcile specific types
p4 reconcile -e //...  # Edited files
p4 reconcile -a //...  # Added files
p4 reconcile -d //...  # Deleted files

# Reconcile to specific changelist
p4 reconcile -c 12345 //...

Common Workflows

Daily Sync Workflow

# 1. Check for open files
p4 opened

# 2. Sync latest
p4 sync

# 3. Resolve any conflicts
p4 resolve

# 4. Continue working

Edit-Submit Workflow

# 1. Open file for edit
p4 edit file.txt

# 2. Make changes
# ... edit file ...

# 3. Verify changes
p4 diff file.txt

# 4. Submit
p4 submit -d "Description of changes"

Add New Files Workflow

# 1. Create files locally
# ... create files ...

# 2. Add to Perforce
p4 add newfile.txt

# 3. Verify
p4 opened

# 4. Submit
p4 submit -d "Add new feature files"

Best Practices

1. Always sync before editing – Avoid conflicts
2. Use descriptive changelist descriptions – Help others understand
3. Submit related changes together – Atomic commits
4. Revert unchanged files with p4 revert -a
5. Check p4 opened before leaving for the day
6. Use p4 reconcile to catch local changes
7. Preview with -n before destructive operations
8. Use exclusive locks for binary files
9. Don’t submit broken code – Test first
10. Keep changelists small – Easier to review/revert

Troubleshooting