hpux man page for m4

m4(1)							      General Commands Manual							     m4(1)

NAME
       m4 - macro processor

SYNOPSIS
       [options] [file ...]

DESCRIPTION
       is  a  macro  processor	intended  as a front end for Ratfor, C, and other languages.  Each of the argument files is processed in order; if
       there are no files, or if a file name is standard input is read.  The processed text is written to standard output.

   Options
       recognizes the following options:

	      Operate interactively.
			Interrupts are ignored and the output is unbuffered.  Using this mode may be very difficult.

	      Enable line sync output for the C preprocessor

	      Change the size of the push-back and argument collection
			buffers from the default of 4,096.

	      Change the size of the symbol table hash array from the
			default of 199.  The size should be prime.

	      Change the size of the call stack from the default of 100 slots.
			Macros take three slots, and nonmacro arguments take one.

	      Change the size of the token buffer from the default of 512 bytes.

	      To be effective, the options listed above must appear before any file names and before any or options.

	      Define	name as val or as null if val is omitted.

	      Undefine	name.

   Macro Calls
       Macro calls have the form:

       The left parenthesis must immediately follow the name of the macro.  If the name of a defined macro is not followed by a it is deemed to be
       a  call	of  that macro with no arguments.  Potential macro names consist of alphabetic letters, digits, and underscore the first character
       cannot be a digit.

       Leading unquoted blanks, tabs, and newlines are ignored while collecting arguments.  Left and right single quotes and  are  used  to  quote
       strings.  The value of a quoted string is the string stripped of the quotes.

       When  a	macro  name is recognized, its arguments are collected by searching for a matching right parenthesis.  If fewer arguments are sup-
       plied than are in the macro definition, the trailing arguments are taken to be null.  Macro evaluation proceeds normally during the collec-
       tion  of  the  arguments, and any commas or right parentheses which happen to turn up within the value of a nested call are as effective as
       those in the original input text.  After argument collection, the value of the macro is pushed back onto the input stream and rescanned.

   Built-In Macro Names
       makes available the following built-in macros.  They can be redefined, but, once this is done, the original meaning is lost.  Their  values
       are null unless otherwise stated.

       Change left and right comment markers from the default
			 and  newline.	 With  no  arguments,  the  comment mechanism is effectively disabled.	With one argument, the left marker
			 becomes the argument and the right marker becomes newline.  With two arguments, both markers are affected.  Comment mark-
			 ers may be up to five characters long.

       Change quote symbols to the first and second arguments.
			 The symbols may be up to five characters long.  without arguments restores the original values (i.e., and

       Returns the value of its argument decremented by 1.

       The second argument is installed as the value of the macro
			 whose name is the first argument.  Each occurrence of in the replacement text, where n is a digit, is replaced by the nth
			 argument.  Argument 0 is the name of the macro; missing arguments are replaced by the null string;  is  replaced  by  the
			 number  of  arguments; is replaced by a list of all the arguments separated by commas; is equivalent to but each argument
			 is quoted (with the current quotes).

       Returns the quoted definition of its arguments.
			 It is useful for renaming macros, especially built-ins.

       maintains 10 output streams, numbered 0 to 9.
			 The final output is the concatenation of the streams in numerical order; initially, stream 0 is the current stream.   The
			 macro changes the current output stream to its (digit-string) argument.  Output diverted to a stream other than 0 through
			 9 is discarded.

       Returns the value of the current output stream.

       Reads and discards characters up to and including the next newline.

       Prints current names and definitions,
			 for the named items, or for all if no arguments are given.

       Prints its argument on the diagnostic output file.

       Evaluates its argument as an arithmetic expression,
			 using 32-bit arithmetic.  Operators include and relationals, and parentheses.	Octal and hexadecimal numbers may be spec-
			 ified	as  in	C.   The second argument specifies the radix for the result; the default is 10.  The third argument may be
			 used to specify the minimum number of digits in the result.

       Is a predefined object with a null value.

       If the first argument is defined,
			 the value is the second argument; otherwise the third.  If there is no third argument, the value is null.   The  word	is
			 predefined on HP-UX system versions of

       Has three or more arguments.
			 If  the  first argument is the same string as the second, then the value is the third argument.  If not, and if there are
			 more than four arguments, the process is repeated with arguments 4, 5, 6 and 7.   Otherwise,  the  value  is  either  the
			 fourth string, or, if it is not present, null.

       Returns the contents of the file named in the argument.

       Returns the value of its argument incremented by 1.
			 The value of the argument is calculated by interpreting an initial digit-string as a decimal number.

       Returns the position in its first argument
			 where the second argument begins (zero origin), or -1 if the second argument does not occur.

       Returns the number of characters in its argument.

       Causes immediate exit from
			 Argument 1, if given, is the exit code; the default is 0.

       Argument 1 is pushed back at final EOF;
			 for example:

       Fills in a string of
			 in its argument with the current process ID.

       Removes current definition of its arguments,
			 exposing the previous one, if any.

       Similar to	 but saves any previous definition.

       Returns all but its first argument.
			 The  other  arguments	are  quoted and pushed back with commas in between.  The quoting nullifies the effect of the extra
			 scan that will subsequently be performed.

       Identical to	 except that it says nothing if the file is inaccessible.

       Returns a substring of its first argument.
			 The second argument is a zero-origin number selecting the first character; the third argument indicates the length of the
			 substring.  A missing third argument is taken to be large enough to extend to the end of the first string.

       Executes the HP-UX system command given in the first argument.
			 No value is returned.

       Is the return code from the last call to

       Turns off trace globally and for any macros specified.
			 Macros specifically traced by can be untraced only by specific calls to

       With no arguments, turns on tracing for all macros
			 (including built-ins).  Otherwise, turns on tracing for named macros.

       Transliterates the characters in its first argument
			 from the set given by the second argument to the set given by the third.  No abbreviations are permitted.

       Removes the definition of the macro named in its argument.

       Causes immediate output of text from diversions named as
			 arguments,  or  all  diversions if no argument.  Text may be undiverted into another diversion.  Undiverting discards the
			 diverted text.

       (XPG4 only.) It is an error to specify an argument containing any non-numeric character for the built-in-macros: and

SEE ALSO
       cpp(1), ratfor(1).

STANDARDS CONFORMANCE
																	     m4(1)