Running a Windows executable file from within R with command line options

Question

I am trying to call a Windows program called AMDIS from within R using the call

system("C:/NIST08/AMDIS32/AMDIS_32.exe /S C:/Users/Ento/Documents/GCMS/test_cataglyphis_iberica/queens/CI23_Q_120828_01.CDF")

in order to carry out an analysis (specified using the /S switch) on a file called CI23_Q_120828_01.CDF, but it seems that no matter what I try the file is not loaded in correctly, presumably because the options are not passed along. Does anyone have a clue what I might be doing wrong?

Right now this command either

1. doesn't do anything,
2. makes AMDIS pop up, but it doesn't load the file I specify

3. gives me the error

   Warning message:

running command 'C:/NIST08/AMDIS32/AMDIS_32.exe /S C:/Users/Ento/Documents/GCMS/test_cataglyphis_iberica/queens/CI23_Q_120828_01.CDF' had status 65535

(I have no idea what results in these different outcomes of the same command)

(the AMDIS command line options are described here at the page 8)

Cheers,
Tom

EDIT:
Found it had to do with forward vs backslashes - running

system("C:\\NIST08\\AMDIS32\\AMDIS_32.EXE C:\\Users\\Ento\\Documents\\GCMS\\test_cataglyphis_iberica\\queens\\CI23_Q_120828_01.CDF /S /E")

seems to work - thank you all for the suggestions!

Answer 1

You've heard of bquote , noquote , sQuote, dQuote , quote enquote and Quotes, well now meet shQuote!!! :-)

This little function call works to format a string to be passed to an operating system shell. Personally I find that I can get embroiled in backslash escaping hell, and shQuote saves me. Simply type the character string as you would on the command line of your choice ('sh' for Unix alikes like bash , csh for the C-shell and 'cmd' for the Windows shell ) wihtin shQuote and it will format it for a call from R using system:

shQuote("C:/NIST08/AMDIS32/AMDIS_32.exe /S C:/Users/Ento/Documents/GCMS/test_cataglyphis_iberica/queens/CI23_Q_120828_01.CDF" , type = "cmd" )
#[1] "\"C:/NIST08/AMDIS32/AMDIS_32.exe /S C:/Users/Ento/Documents/GCMS/test_cataglyphis_iberica/queens/CI23_Q_120828_01.CDF\""

More generally, you can use shQuote like this:

system( shQuote( "mystring" , type = c("cmd","sh") ) , ... )