forked from GitHub/gf-core
The system_pipe (aka "?") command creates a temporary file _tmpi containing the input of the system command. It *both* appends _tmpi as an extra argument to the system command line *and* adds an input redirection "< _tmpi". (It also uses and output redirection "> _tmpo" to captures the output of the command.) With this patch, the _tmpi argument is no longer appended to the command line. This allows system_pipe to work with pure filters, such as the "tr" commands, but it will no longer work with commands that require an input file name. (It is possible to use write_file instead...) TODO: it would also be fairly easy to eliminate the creation of the _tmpi and _tmpo files altogether.