Am Freitag, 2. September 2005 12:10 schrieb Erik Leunissen: > L.S. > > I would like to compile C code by feeding it to gcc (or cc) from stdin, > instead of specifying an input file. What I want would result in a > command line like: > > echo "ThisWouldNeedToBeCcode" | gcc -o out.o > > > (Note aside: > This may look as an awkward or even useless construct at first glance. > However that's not the point. I supplied this example invocation to keep > the case simple and to the point. In reality I want to invoke such a > command from a scripting language, where not using files for input does > make sense. I do not want to clutter this case with issues regarding the > scripting language.) > > > The above command line and several variants that I tried, evoke the > following complaint: > > gcc: no input files > > which, of course, is very much true. > > > Is reading from stdin simply not supported? > > > In case it is relevant, here's the output from "gcc -v": > > Reading specs from /usr/lib/gcc-lib/i586-suse-linux/3.3.1/specs > Configured with: ../configure --enable-threads=posix --prefix=/usr > --with-local-prefix=/usr/local --infodir=/usr/share/info > --mandir=/usr/share/man --libdir=/usr/lib > --enable-languages=c,c++,f77,objc,java,ada --disable-checking > --enable-libgcj --with-gxx-include-dir=/usr/include/g++ > --with-slibdir=/lib --with-system-zlib --enable-shared > --enable-__cxa_atexit i586-suse-linux > Thread model: posix > gcc version 3.3.1 (SuSE Linux) > > > > Thanks in advance for any help, > > Erik Leunissen > ============== If you try to feed gcc with stdin by specifing the input file as '-' (as it is wide spread standart) gcc tells you : echo "some input"|gcc - gcc: -E required when input is from standard input which means (-E) only to execute the preprocessor state. This reflects that only the preprocessor works as a simple stdin/stdout filter and that gcc, in common is a wrapper around several programs that will write temporary files anyway (if not suppressed by "-pipe"). This also makes sense, since a compile process is NOT progressive but final, which means you need a closed file to be compiled into an object file. I would recommend to write an own wrapper producing the result you want: gcc_stdin_wrap.sh: #!/bin/sh cat - > /tmp/tmp_file_name.c gcc -c -o $* /tmp/tmp_file_name.c rm /tmp/tmp_file_name.c Of course you can add much more features (security !) to this script. BYE INGO
