Shell Tips !

In our list of “CLI workaround for Windows XP“, a missing command is GREP. Now, you can have a GREP-Like command with the DOS command QGREP. Get the Windows Server 2003 Resource Kit tools on microsoft.com.

# display help

QGREP /?

usage: qgrep [-?BELOXlnzvxy][-e string][-f file][-i file][strings][files]
-? - print this message
-B - match pattern if at beginning of line
-E - match pattern if at end of line
-L - treat search strings literally (fgrep)
-O - print seek offset before each matching line
-X - treat search strings as regular expressions (grep)
-l - print only file name if file contains match
-n - print line number before each matching line
-z - print matching lines in MSC error message format
-v - print only lines not containing a match
-x - print lines that match exactly (-BE)
-y - treat upper and lower case as equivalent
-e - treat next argument literally as a search string
-f - read search strings from file named by next argument (- = stdin)
-i - read file list from file named by next argument (- = stdin)
White space separates search strings unless the argument is prefixed with -e, e.g., ‘qgrep “all out” x.y’ means find either “all” or “out” in x.y, while ‘qgrep -e “all out” x.y’ means find “all out”.

# Example for UNIX-Like regexp search

QGREP -X “[a-Z]” MYFILE.TXT

System Requirements

If you are an addict of the command line interface whateve the OS you use, you probably already had difficulties to administrate some Windows XP box remotely. Tips ! Get the Windows Server 2003 Resource Kit tools on microsoft.com you could install lot of usefull tools and especially tail !

# display help

tail /?

# display last ten lines of a file

tail FILENAME

# display last thirty lines of a file

tail -30 FILENAME

# keep accessing file, displaying new lines as necessary.

tail -f FILENAME

System Requirements

When you import file from Windows OS (or even from old Macintosh OS) you most likely have the ^M at the end of each line. Systems based on ASCII or a compatible character set use either LF (Line Feed, 0×0A, n) or CR (Carriage Return, 0×0D, r) individually, or CR followed by LF (CR+LF, 0×0D 0×0A, rn). Below is a quick list of OS using which convention :

• LF : UNIX and UNIX-Like systems, Linux, AIX, Xenix, Mac OS X, BeOS, Amiga, RISC OS…
• CR+LF : CP/M, MP/M, DOS, OS/2, Microsoft Windows (all versions)
• CR : Commodore machines, Apple II family and Mac OS through version 9

The different newline conventions often cause text files that have been transferred between systems of different types to be displayed incorrectly. For example, files originating on Unix or Apple Macintosh systems may appear as a single long line on a Windows system. Conversely, when viewing a file from a Windows computer on a Unix system, the extra CR may be displayed as ^M at the end of each line or as a second line break.
You can convert with editors relatively small files. For larger files on Windows NT/2000/XP you can use the following command:

TYPE unix_file | FIND “” /V > dos_file

On Unix, a DOS/Windows text file can be converted to Unix format by simply using the tool dos2unix or by removing all ASCII CR characters with the command “tr“.

tr -d ‘\r’ < inputfile > outputfile

You can add an alias to your shell startup script to create easy to remember variations of the tr command for each purpose.

Using bash as an example, edit .bashrc and add these lines.

alias cvtCR=”tr ‘\r’ ‘\n’ ”
alias cvtCRLF=”tr -d ‘\r’ “

You now have two new commands that you can type from the command line.
To try the commands out right away, without opening a new terminal, you
need to tell bash to re-read it’s startup file by typing

source .bashrc

Now you are ready to try out the new commands.

To convert an old MAC file you would type
cvtCR < MACFILE > UNIXFILE This will read a file named MACFILE and create a file named UNIXFILE that has all of the r’s converted to n’s For DOS files, you just want to remove the darn r’s so in cvtCRLF the -d tells tr to delete them. If you wan to update a sample file you can use you favorite editor : VI !

:%s/^M//g

Becarefull, you get the cariage return symbols by the keystroke CTRL+V+ENTER.