(autocf21.info.gz) Generic Functions

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 4.3.2 Generic Function Checks
 -----------------------------
 
 These macros are used to find functions not covered by the particular
 test macros.  If the functions might be in libraries other than the
 default C library, first call `AC_CHECK_LIB' for those libraries.  If
 you need to check the behavior of a function as well as find out
 whether it is present, you have to write your own test for it (
 Writing Tests).
 
  -- Macro: AC_CHECK_FUNC (FUNCTION, [ACTION-IF-FOUND [,
           ACTION-IF-NOT-FOUND]])
      If C function FUNCTION is available, run shell commands
      ACTION-IF-FOUND, otherwise ACTION-IF-NOT-FOUND.  If you just want
      to define a symbol if the function is available, consider using
      `AC_CHECK_FUNCS' instead.  This macro checks for functions with C
      linkage even when `AC_LANG_CPLUSPLUS' has been called, since C++ is
      more standardized than C is.  ( Language Choice, for more
      information about selecting the language for checks.)
 
  -- Macro: AC_CHECK_FUNCS (FUNCTION... [, ACTION-IF-FOUND [,
           ACTION-IF-NOT-FOUND]])
      For each given FUNCTION in the whitespace-separated argument list
      that is available, define `HAVE_FUNCTION' (in all capitals).  If
      ACTION-IF-FOUND is given, it is additional shell code to execute
      when one of the functions is found.  You can give it a value of
      `break' to break out of the loop on the first match.  If
      ACTION-IF-NOT-FOUND is given, it is executed when one of the
      functions is not found.
 
  -- Macro: AC_REPLACE_FUNCS (FUNCTION...)
      Like calling `AC_CHECK_FUNCS' using an ACTION-IF-NOT-FOUND that
      adds `FUNCTION.o' to the value of the output variable `LIBOBJS'.
      You can declare a function for which your replacement version is
      used by enclosing the prototype in `#ifndef HAVE_FUNCTION'.  If
      the system has the function, it probably declares it in a header
      file you should be including, so you shouldn't redeclare it, lest
      your declaration conflict.
 

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(autocf21.info.gz) Particular Functions

(autocf21.info.gz) Library Functions