A pragma is an implementation-defined instruction to the compiler. It has the general form:
#pragma directive syntax .--------------------. V | >>-#--pragma--+------+----character_sequence-+--new-line------->< '-STDC-'
The character_sequence is a series of characters giving a specific compiler instruction and arguments, if any. The token STDC indicates a standard pragma; consequently, no macro substitution takes place on the directive. The new-line character must terminate a pragma directive.
The character_sequence on a pragma is subject to macro substitutions. For example,
#define XX_ISO_DATA isolated_call(LG_ISO_DATA) // ... #pragma XX_ISO_DATA
More than one pragma construct can be specified on a single pragma directive. The compiler ignores unrecognized pragmas.
Standard C pragmas are described in Standard pragmas .
Pragmas available for XL C/C++ are described in "General purpose pragmas".