Lately I’ve been doing more work on Windows platforms and I’ve been missing the Linux command line. I’m a huge user of cat, sed, awk and most of all grep. I’m also a huge bash script writer to help with everyday issues. Recently I started playing around with Windows PowerShell and so I’ll be starting to list PowerShell tips from time to time. No I haven’t totally gone to the dark side, I’m still a huge Linux user, but PowerShell does seem like a nice option when you have to use Windows.
So, my latest issue is I needed to search through lots of logs to find an email address. Normally I’d use grep to parse through the files. Instead I opened up a Powershell prompt and used the following command
findstr /I my@email.com logfile.log
Findstr is just like grep and has a lot of the same options. The /I tells it to be case-insensitive. The my@email.com is what I’m looking for in logfile.log. Here are the different settings that you can use:
FINDSTR [/B] [/E] [/L] [/R] [/S] [/I] [/X] [/V] [/N] [/M] [/O] [/P] [/F:file]
[/C:string] [/G:file] [/D:dir list] [/A:color attributes] [/OFF[LINE]]
strings [[drive:][path]filename[ ...]]/B Matches pattern if at the beginning of a line.
/E Matches pattern if at the end of a line.
/L Uses search strings literally.
/R Uses search strings as regular expressions.
/S Searches for matching files in the current directory and all
subdirectories.
/I Specifies that the search is not to be case-sensitive.
/X Prints lines that match exactly.
/V Prints only lines that do not contain a match.
/N Prints the line number before each line that matches.
/M Prints only the filename if a file contains a match.
/O Prints character offset before each matching line.
/P Skip files with non-printable characters.
/OFF[LINE] Do not skip files with offline attribute set.
/A:attr Specifies color attribute with two hex digits. See “color /?”
/F:file Reads file list from the specified file(/ stands for console).
/C:string Uses specified string as a literal search string.
/G:file Gets search strings from the specified file(/ stands for console).
/D:dir Search a semicolon delimited list of directories
strings Text to be searched for.
[drive:][path]filename
Specifies a file or files to search.Use spaces to separate multiple search strings unless the argument is prefixed
with /C. For example, ‘FINDSTR “hello there” x.y’ searches for “hello” or
“there” in file x.y. ‘FINDSTR /C:”hello there” x.y’ searches for
“hello there” in file x.y.Regular expression quick reference:
. Wildcard: any character
* Repeat: zero or more occurrences of previous character or class
^ Line position: beginning of line
$ Line position: end of line
[class] Character class: any one character in set
[^class] Inverse class: any one character not in set
[x-y] Range: any characters within the specified range
\x Escape: literal use of metacharacter x
\<xyz Word position: beginning of word
xyz\> Word position: end of wordFor full information on FINDSTR regular expressions refer to the online Command
Reference.
