Use repeated -e options to search for multiple alternatives: grep -e 'error' -e 'warning' file.log. By default, grep selects a line when any supplied pattern matches—not only when every term appears. Choose -F for literal text, -E for extended regular-expression alternatives, or -f to load patterns from a file.
Search for any of several words or patterns
Give grep each pattern with its own -e option:
grep -e 'error' -e 'warning' file.logThis prints lines in file.log containing either error or warning. Multiple patterns are alternatives: a line is selected if any specified pattern matches. The order in which grep evaluates them is unspecified by POSIX. See The Open Group’s POSIX grep specification.
Quoting each pattern keeps the shell from interpreting characters before grep receives them. Single quotes are a practical choice when the pattern does not need shell variable expansion. GNU grep recommends quoting patterns in shell commands; its -e option also makes a pattern beginning with a dash unambiguous. See the GNU grep matching-control documentation.
Choose literal strings or regular expressions
| What you need | Command | How it treats the patterns |
|---|---|---|
| Several literal strings | grep -F -e 'literal.text' -e 'other[thing]' file.txt |
Matches the characters as written; punctuation is not treated as regular-expression syntax. |
| Regex alternatives | grep -E 'error|warning|failed' file.log |
Uses extended regular expressions, where | means “or.” |
| Default/basic regular expressions | grep -e 'error' -e 'warning' file.log |
Uses basic regular expressions unless another mode is selected; separate -e patterns remain alternatives. |
Use -F when a pattern contains punctuation that should be matched literally. Use -E when you want to compose alternatives in one regular expression. Plain grep uses basic regular expressions by default, whose notation differs from extended regular expressions. The GNU grep regular-expression documentation describes basic, extended, fixed-string, and Perl-compatible modes.
Free tools Windows power users keep installed
One-click scans. No signup required.
#1 Best Overall
- Read Before You Buy — No Video Output: These adapters support charging and USB 2.0 data transfer, but cannot transmit video signals. Except for standard USB webcams (which use USB data only), they are not compatible with HDMI/DisplayPort cables, video-capable USB-C hubs, or docking stations with video output.
- Convert USB-A Ports to USB-C: Designed to connect USB-C earphones, cables, flash drives, card readers, and other USB-C accessories to standard USB-A ports. Plug-and-play with no drivers or software required.
- Aluminum Alloy Housing: Built with a sturdy aluminum alloy shell that aids in heat dissipation and protects against daily wear and scratches. Designed to maintain a stable and secure connection.
- Compact & Travel-Friendly: The ultra-compact design allows the adapter to stay plugged into your device without blocking adjacent ports or adding bulk, reducing wear and tear on your original USB ports.
- 12-Month Warranty: Backed by a 12-month manufacturer warranty for peace of mind. Designed to meet strict quality control standards for reliable everyday performance.
Search a saved list of patterns
Put one pattern per line in a file such as patterns.txt, then pass it with -f:
grep -f patterns.txt file.txtIf each entry is literal text rather than a regular expression, combine -f with -F:
Rank #2
- 5-in-1 USB-C Hub: Experience comprehensive connectivity featuring a Power Delivery input, two USB-A 2.0 ports, a USB-A 3.0 port, and an HDMI port. (Note: The USB-C power delivery input port is only for connecting an external wall charger to power your laptop and cannot power peripheral devices.)
- 90W Pass-Through Charging: Achieve optimal charging with 90W pass-through power to your laptop, supported by a total input of 100W, with the hub reserving 10W for operational efficiency. (Note: Wall charger not included.)
- Quick Data Transfers: Accelerate your productivity with rapid data transfers using a high-speed 5Gbps USB 3.0 port and two 480Mbps USB 2.0 ports.
- 4K HDMI Display: Enhance your visual experience with a hub capable of delivering 4K resolution at 30Hz in both mirror and extend modes. Please note that this hub is compatible with MacBook (macOS 12 and newer), Windows 10 and 11, ChromeOS, and laptops equipped with DP Alt Mode and Power Delivery. Note: This device is not compatible with Linux.
- What You Get: Anker USB-C Hub (5-in-1, 4K HDMI), welcome guide, 18-month warranty, and our friendly customer service.
grep -F -f patterns.txt file.txtThis is useful for a long list or one you reuse. GNU grep accepts patterns through -e and -f; patterns in a file are separated by newlines. A blank pattern line can match every line, so remove unintended empty entries. The empty basic regular expression behavior is described in The Open Group grep(1p) reference.
Require every term on the same line
Repeated -e options do not mean “match all.” For a simple same-line AND condition, filter the first result through another grep:
Quick wins for a faster PC:
Fix the driver behind crashes, sound loss and screen glitchesFind Drivers →Repair Windows errors before they cause bigger problemsFix Now →Scan for outdated or missing drivers - takes under a minuteDriver Scan →Rank #3
- Sleek 7-in-1 USB-C Hub: Features an HDMI port, two USB-A 3.0 ports, and a USB-C data port, each providing 5Gbps transfer speeds. It also includes a USB-C PD input port for charging up to 100W and dual SD and TF card slots, all in a compact design.
- Flawless 4K@60Hz Video with HDMI: Delivers exceptional clarity and smoothness with its 4K@60Hz HDMI port, making it ideal for high-definition presentations and entertainment. (Note: Only the HDMI port supports video projection; the USB-C port is for data transfer only.)
- Double Up on Efficiency: The two USB-A 3.0 ports and a USB-C port support a fast 5Gbps data rate, significantly boosting your transfer speeds and improving productivity.
- Fast and Reliable 85W Charging: Offers high-capacity, speedy charging for laptops up to 85W, so you spend less time tethered to an outlet and more time being productive.
- What You Get: Anker USB-C Hub (7-in-1), welcome guide, 18-month warranty, and our friendly customer service.
grep -e 'error' file.log | grep -e 'timeout'The first command selects lines containing error; the second keeps only those selected lines that also contain timeout.
Keep scripts portable
For portability across POSIX-compatible grep implementations, use the standardized options -e, -f, -E, and -F, and stick to the intended POSIX regular-expression syntax. GNU grep also offers -P for Perl-compatible regular expressions, but that mode is not the portable default and may not be available in other implementations. Check the local manual before depending on implementation-specific options. The GNU manual consulted is for grep 3.12; the cited POSIX specification is POSIX.1-2017.
Quick Recap
Best Value
- 5-in-1 Connectivity: Equipped with a 4K HDMI port, a 5 Gbps USB-C data port, two 5 Gbps USB-A ports, and a USB C 100W PD-IN port. Note: The USB C 100W PD-IN port supports only charging and does not support data transfer devices such as headphones or speakers.
- Powerful Pass-Through Charging: Supports up to 85W pass-through charging so you can power up your laptop while you use the hub. Note: Pass-through charging requires a charger (not included). Note: To achieve full power for iPad, we recommend using a 45W wall charger.
- Transfer Files in Seconds: Move files to and from your laptop at speeds of up to 5 Gbps via the USB-C and USB-A data ports. Note: The USB C 5Gbps Data port does not support video output.
- HD Display: Connect to the HDMI port to stream or mirror content to an external monitor in resolutions of up to 4K@30Hz. Note: The USB-C ports do not support video output.
- What You Get: Anker 332 USB-C Hub (5-in-1), welcome guide, our worry-free 18-month warranty, and friendly customer service.
Rank #4
- Dual Converters, Infinite Potential：Includes 2× USB C male to USB A female adapters and 2× USB A male to USB C female adapters. Perfect for a wide range of uses—tablets with Bluetooth keyboards, expand USB ports on macbook, and more. Two different converters for all your daily needs
- Next-Level 10Gbps & 3A Charging: No more slow 480Mbps, this usb to usb c adapter has a transfer speed of up to 10Gbps, allowing you to do more transferring in less time. This usb adapter fits both USB A and USB C charger, supporting up to 3A fast charging
- Upgraded Exquisite Craftsmanship: With an aluminum alloy housing and metal connector, the usbc to usb adapter is extremely durable and sturdy. Rigorously tested to withstand more than 10,000 times of plugging and unplugging, ensuring long-lasting performance
- Broad Compatible: The usb c to usb adapter widely supports all USB C/ USB A devices like laptops, tablets, cellphones, car chargers, and phone chargers. Such as compatible with MacBook Pro/Air 2023/2022, Thunderbolt 4/3 Devices,Apple MagSafe Watch 9/8/7/SE/Ultra, iPad Pro 2022/2021, Samsung Galaxy S23/S20/S10, and iPhone 17/16/15 Pro. Plug and play
- Please Note: To reach 10Gbps speed, keep the cable under 3.3 ft. For USB A Male to USB C adapters, try flipping the USB C connector. USB C Male to USB A adapters support bidirectional 10Gbps transfer within 3.3 ft
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon at the time of purchase will apply.
