Spec manual

It aims to help you gradually learn the language. It defines the language. So if you need the most trustworthy source of information about the language details, the specification is the right place. A new specification version is released every year. All these resources are useful in real-life development, as they contain valuable information about language details, their support etc.

Please remember them or this page for the cases when you need in-depth information about a particular feature. The current working directory is included in the list of directories scanned.

Current argument is the name of a linker script. Search for that file in the current list of directories to scan for libraries. If the file is located insert a --script option into the command line followed by the full path name found. If the file is not found then generate an error message. Note: the current working directory is not searched.

Print str as an error message. Use this when inconsistent options are detected. Process the asm spec. This is used to compute the switches to be passed to the assembler. This is a spec string for passing switches to an assembler post-processor, if such a program is needed. Process the link spec. This is the spec for computing the command line passed to the linker.

Dump out a -L option for each directory that GCC believes might contain startup files. If the target supports multilibs then the current multilib directory is prepended to each of these paths. Process the lib spec. This is a spec string for deciding which libraries are included on the command line to the linker. Process the libgcc spec. This is a spec string for deciding which GCC support library is included on the command line to the linker.

Process the startfile spec. This is a spec for deciding which object files are the first ones passed to the linker. Typically this might be a file named crt0. Process the endfile spec. This is a spec string that specifies the last object files that are passed to the linker. Process the cpp spec. This is used to construct the arguments to be passed to the C preprocessor.

Process the cc1 spec. This is used to construct the options to be passed to the actual C compiler cc1. Process the cc1plus spec. Substitute the variable part of a matched option. Note that each comma in the substituted string is replaced by a single space.

Remove all occurrences of -S from the command line. Note—this command is position dependent. Call the named function function , passing it args. The function returns a string which is processed as if it had appeared literally as part of the current spec.

The getenv spec function takes two arguments: an environment variable name and a string. If the environment variable is not defined, a fatal error is issued.

Otherwise, the return value is the value of the environment variable concatenated with the string. The if-exists spec function takes one argument, an absolute pathname to a file.

If the file exists, if-exists returns the pathname. Here is a small example of its usage:. The if-exists-else spec function is similar to the if-exists spec function, except that it takes two arguments. The standard four-circle diffractometer supports many advanced modes and includes features such as least-squares refinement of the lattice parameters. New geometry configurations can be created. Hardware configuration employs a spread-sheet-style interface to select device names, addresses, motor parameters, etc.

Security features let site administrators restrict access to particular motors such as those at a synchrotron beam-line front end. Online documentation spec manual spec help pages spec guides hardware guide.