/*
	numeric() is useful in while's, if's, etc., but don't use *p++
	max() and min() depend on the types of the operands
	abs() is absolute value
*/
# define numeric(c)		(c >= '0' && c <= '9')
# define max(a,b) 		(a<b ? b : a)
# define min(a,b) 		(a>b ? b : a)
# define abs(x)			(x>=0 ? x : -x)

# define copy(srce,dest)	cat(dest,srce,0)
# define compare(str1,str2)	strcmp(str1,str2)
# define equal(str1,str2)	!strcmp(str1,str2)
# define length(str)		strlen(str)
# define size(str)		(strlen(str) + 1)

/*
	The global variable Statbuf is available for use as a stat(II)
	structure.  Note that "stat.h" is included here and should
	not be included elsewhere.
	Exists(file) returns 0 if the file does not exist;
	the flags word if it does (the flags word is always non-zero).
*/
# include <sys/types.h>
# include <sys/stat.h>
struct stat Statbuf;
# define exists(file)		(stat(file,&Statbuf) < 0 ? 0 : Statbuf.st_mode)

/*
	libS.a interface for xopen() and xcreat()
*/
# define xfopen(file,mode)	fdfopen(xopen(file,mode),mode)
# define xfcreat(file,mode)	fdfopen(xcreat(file,mode),1)

# define remove(file)		xunlink(file)

/*
	SAVE() and RSTR() use local data in nested blocks.
	Make sure that they nest cleanly.
*/
# define SAVE(name,place)	{ int place name;
# define RSTR(name,place)	name = place;}

/*
	Use: DEBUG(sum,d) which becomes fprintf(stderr,"sum = %d\n",sum)
*/
# define DEBUG(variable,type)	fprintf(stderr,"variable = %type\n",variable)

/*
	Use: SCCSID(%W%) which becomes static char Sccsid "%W%"
*/
# define SCCSID(arg)		static char Sccsid[] "arg"

/*
	Use of ERRABORT() will cause libS.a internal
	errors to cause aborts
*/
# define ERRABORT()	_error() { abort(); }

/*
	Use of USXALLOC() is required to force all calls to alloc()
	(e.g., from libS.a) to call xalloc().
*/
# define USXALLOC()	alloc(n) {return(xalloc(n));} free(n) {xfree(n);} \
		malloc(n) {register p; p=xalloc(n); return(p != -1?p:0);}

# define NONBLANK(p)		while (*p==' ' || *p=='\t') p++


/*
	A global null string.
*/
char	Null[1];

/*
	A global error message string.
*/
char	Error[128];