xc -- portable IRAF compile/link utility
xc [flags] files
- To support VMS link options file. Next file is taken to be the VMS name of a link options file. This is primarily for using long lists of files or libraries and not for actual VMS Linker options, since XC adds continuation characters where it believes it is appropriate.
- Tells fortran to do array bound and other checking. By default no checking is done. From DCL fortran usually does array and overflow checking which is not used here.
- Tells xc not to link, i.e., not to create an executable.
- Causes debug messages to be printed during execution.
- -F, -f
- Do not delete the Fortran translation of an SPP source file.
- Generates debugging information and (for VMS), links in the debugger.
- Causes the executable to be linked as a host program, i.e., without the IRAF main and without searching the IRAF libraries, unless explicitly referenced on the command line. Used to compile and link host (e.g., Fortran) programs which may or may not reference the IRAF libraries.
- Tells fortran to use I*2 by default.
- Tells fortran to use I*4 by default.
- This tells the linker which libraries besides the standard ones to include. These must be either on the current directory, or in an IRAF system library (lib$ or hlib$). The library specification must be immediately after the option as in "-lxtools". No other option may follow the l option in the same argument as in -lxtoolsO.
- Creates a list file. VMS specific.
- -M, -m
- Tells the linker to create a link map.
- Not really supported under VMS since "normal" users cannot install images. In Unix this is just a link option to make a shareable image.
- Same as -z for VMS.
- -Nh [filename]
- This tells xpp that the foreign definitions in the file specified should be used in preference to standard include files.
- This flag redirects the output of the compile if used in conjunction with -c option or specifies where the executable or object is to be placed. If not given the first file name is used to obtain the name for the executable or object.
- Optimize object code produced; this is now the default, but this switch is still provided for backwards compatibility.
- -p pkgname
- Load the package environment for the named external package, e.g., "xc -c -p noao file.x". If the same package is always specified the environment variable or logical name PKGENV may be defined at the host level to accomplish the same thing. The package name must be specified when doing software development in an external or layered package.
- Check portability. This should be used all of the time in IRAF, but the VMS C compiler forces the use of non-standard constructs in some cases. Also <stdio.h> and <ctype.h> get complaints for the above reason. This may be used and probably should when working with Fortran due to Dec non-standard extension.
- Disable optimization. Opposite of -O. Object code will be optimized by default.
- Strips all symbols and debugging information.
- Same as -s for VMS.
- Verbose mode. Causes messages to be printed during execution telling what the xc program is doing.
- Suppress warnings.
- -X, -x
- Compile and link for debugging. In VMS/IRAF, links in the VMS debugger and symbols.
- Create a non-shareable image (default).
XC is a machine independent utility for compiling and linking IRAF tasks or files. The XC utility may also be used to compile and/or link non-IRAF files and tasks. The VMS version of XC supports all of the important flags except -D which VMS C doesn't support in any way. It can be used to generate fortran from xpp or ratfor code, to compile any number of files, and then link them if desired. XC accepts and maps IRAF virtual filenames, but since it is a standalone bootstrap utility the environment is not passed, hence logical directories cannot be used.
The following extensions are supported by the VMS version of xc: It is suggested that everyone stick with the iraf virtual file name extensions. These are : .x, .r, .f, .c, .s, .o, .a, .e. The mapping of these to their VMS counterparts is:
.x -> .x SPP code .r -> .r Ratfor code .f -> .for Fortran code .c -> .c C code .s -> .mar Macro assembler code .o -> .obj Object module .a -> .olb Library file .e -> .exe Executable Image
XC is available both in the CL, via the foreign task interface, and as a standalone DCL callable task. Usage is equivalent in either case. Upper case flags must be quoted to be recognized (the upper case flags will be done away with at some point).
Any upper case flags in the following examples must be doubly quoted in the CL, singly quoted in VMS, to make it to XC without VMS mapping everything to one case. Omit the "-x" flag on a UNIX system.
1. Compile and link the source file "mytask.x" to produce the executable "mytask.e".
cl> xc mytask.x
2. Translate the file "file.x" into Fortran.
cl> xc -f file.x
3. Compile but do not link "mytask.x" and the support file "util.x".
cl> xc -c file.x util.x
4. Now link these for debugging.
cl> xc -x file.o util.o
5. Link the same files without the VMS debug stuff, but link in the library -ldeboor (the DeBoor spline routines) as well.
cl> xc file.o util.o -ldeboor
XC is often combined with mkpkg to automatically maintain large packages or libraries.
The -S flag should generate assembler output but does not presently do so in the VMS version. All case sensitive switches should be done away with in both the UNIX and VMS versions of the utility.