Pharo Script of the Day: Execute command in a MSYS2 MinGW64 context

For this to work first ensure you have the MSYS2 bin directory added to the PATH environment variable. Just run the following from command line and add "c:\msys64\usr\bin\" to the end of the PATH variable:

systempropertiesadvanced

We will use ProcessWrapper, although with limited features, it works perfectly for simple tasks. And now you can run all those complex bash shell commands from Pharo :) For example to get the CPU frequencies in GHz:

| process output answer cmd |

process := ProcessWrapper new.
cmd := '"{ echo scale=2; awk ''/cpu MHz/ {print $4 "" / 1000""}'' /proc/cpuinfo; } | bc"'.
output := process
 useStdout;
 useStderr;
 startWithShellCommand: 'set CHERE_INVOKING=1 & set MSYSTEM=MINGW64 & set MSYS2_PATH_TYPE=inherit & "c:\msys64\usr\bin\bash.exe" -c ' , cmd;
 upToEnd.
^ (answer := process errorUpToEnd) isEmpty not
 ifTrue: [ answer ]
 ifFalse: [ output ].

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Pharo Script of the Day: Sort a column in a CSV file

Hi there. Today I wanted to translate to Pharo Smalltalk the code in a Bash one-liner to sort a column in a CSV file:

cat myfile.txt | cut -d \; -f 2 | sort

For replicating this one, you will need the NeoCSV package (doc), and just use the power of SortedCollection:

SortedCollection streamContents: [ : out |
 'myfile.txt' asFileReference readStreamDo: [ : in |
  (NeoCSVReader on: (ZnBufferedReadStream on: in)) in: [ : reader |
   reader 
    separator: $;;
    do: [ : each | out nextPut: each second ] ] ] ].

which you can apply to a dummy myfile.txt CSV:

a;Rachmaninoff;1
b;Horowitz;2
c;Hofmann;3
d;Scriabin;4

Hope you liked it.

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