# The ultimate cURL cheatsheet for developers and sysadmins.

# Quickly find commands to download files, test REST APIs, send POST/GET requests,

# and set custom headers with practical, copy-paste examples.

# ----- A Practical `curl` Cheatsheet -----

# Simply fetch the content of a URL (GET request):

xinit@localhost:~$ curl https://example.com

# Show detailed info, including response headers (-i):

xinit@localhost:~$ curl -i https://example.com

# Show ONLY the response headers (-I or --head):

xinit@localhost:~$ curl -I https://example.com

# Follow redirects (-L for Location):

# Useful for shortened URLs or sites that redirect from http to https.

xinit@localhost:~$ curl -L https://t.co/shortlink

# ----- Advanced Requests -----

# Send a POST request with data (-X POST -d '...'):

xinit@localhost:~$ curl -X POST -d 'param1=value1&param2=value2' https://api.example.com/data

# Send a POST request with JSON data and set content type header (-H):

xinit@localhost:~$ curl -X POST -H "Content-Type: application/json" -d '{"key":"value"}' https://api.example.com/json

# Send a request with a custom header (e.g., Authorization):

xinit@localhost:~$ curl -H "Authorization: Bearer YOUR_API_TOKEN" https://api.example.com/secure

# Use basic authentication (user:password):

xinit@localhost:~$ curl -u myuser:mypassword https://api.example.com/login

# ----- Working with Data & Files -----

# Download a file and save it with its original name (-O):

xinit@localhost:~$ curl -O https://example.com/drivers/installer.iso

# Download a file and save it with a custom name (-o):

xinit@localhost:~$ curl -o my_installer.iso https://example.com/drivers/installer.iso

# Silently download a file (no progress meter) and show errors (-sS):

xinit@localhost:~$ curl -sS -O https://example.com/script.sh

# Test if an API endpoint is reachable and measure performance (-o /dev/null):

# Throws away the output, but shows connection times and stats.

xinit@localhost:~$ curl -s -o /dev/null -w "%{http_code} | %{time_total}s\n" https://api.example.com/health