tr command causes problems in cygwin bash.exe shell, but works in mintty.exe
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I use Windows with cygwin. The following command works when I use the mintty.exe shell:

    echo ./bootstrp3.cab | tr -cd / | wc -c

Unfortunately it outputs the following message with the bash.exe shell

    Usage:
    tr [-cs] string1 string2
    tr -s[-c] string1
    tr -d[-c] string1
    tr -ds[-c] string1 string2

It seems that the two shells behave differently, but they both seem to be the same kind of shell, because when I `echo $0`, bash.exe outputs `bash` and mintty.exe outputs `-bash`.

I also tried the command with the bourne shell (sh.exe), but it outputs the same message as with the bash.exe shell.

Does anyone know how I can get the command working with the sh.exe or bash.exe shell? And does someone know why the two bash shells behave differently?