Windows
Linux
Text Processing
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Windows findstr /r (regex) equivalent in Linux
Searches text using extended regular expressions for complex pattern matching.
Windows
→
findstr /r (regex)
Linux equivalents
grep -E
grep -E
grep -E
Overview
What this command does
Searches text using extended regular expressions for complex pattern matching.
Migration tip:
grep -E enables extended regex with +, ?, |, and () without backslashes. Use grep -P for full Perl-compatible regex.Practical tasks
Common use cases
Search using extended regular expressions
Searches text using extended regular expressions for complex pattern matching.
grep -E 'pat1|pat2'
Match either pattern
grep -E '^[0-9]+'
Lines starting with digits
grep -oE '[0-9.]{7,15}'
Extract IP-like patterns
Ready to run
Copyable Linux commands
Review paths, device names, package names and permissions before running any command.
grep -E 'ERROR|WARN|CRIT' app.log
grep -oE '[0-9]{1,3}(\.[0-9]{1,3}){3}' access.log
grep -Ev '^#|^$' /etc/ssh/sshd_config
Walkthrough
Examples with explanations
# Windows: findstr /r "error\|warn" file.txt
# Match multiple patterns:
grep -E 'ERROR|WARN|CRIT' app.log
# Extract all IP addresses:
grep -oE '[0-9]{1,3}(\.[0-9]{1,3}){3}' access.log
# Config file without comments or blanks:
grep -Ev '^#|^$' /etc/ssh/sshd_configReference
Common options and variations
| Command or option | Use |
|---|---|
grep -E 'pat1|pat2' | Match either pattern |
grep -E '^[0-9]+' | Lines starting with digits |
grep -oE '[0-9.]{7,15}' | Extract IP-like patterns |
grep -Ev '^#|^$' | Skip comment and blank lines |
Distro differences
Debian/Ubuntu vs Fedora vs Arch
This command is the same on Debian/Ubuntu, Fedora and Arch Linux when the relevant tool is installed.
| Distribution | Package manager / base | Equivalent command | Difference to notice |
|---|---|---|---|
| Debian/Ubuntu | same command | grep -E |
Same command on this distribution. |
| Fedora | same command | grep -E |
Same command on this distribution. |
| Arch | same command | grep -E |
Same command on this distribution. |
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