search_executable: Search the working directory and the run path for an executable
Description
This function tries to find a binary of a given name by looking
in the current working directory and the directories listed in
the $PATH environment variable. If an environment variable with
name equal to to binaries name in upper case is given, it also
tries to use this as path of the binary.
Usage
search_executable(name, envir_var = NULL)
Arguments
name
The name of the executable to look for
envir_var
the name of the environment variable to use
Value
The complete path of the executable is found, or "NULL" if not.