6437624 RFE: Add ksh93 (as /usr/bin/ksh93) and libshell.so to OS/Net

6505835 AST tools and library (libpp) required for creating l10n messages for ksh93
PSARC/2006/550 Korn Shell 93 Integration
PSARC/2006/587 /etc/ksh.kshrc for ksh93
PSARC/2007/035 ksh93 Amendments
Contributed by Roland Mainz <roland.mainz@nrubsig.org>

--HG--
rename : usr/src/lib/libcmd/common/mapfile-vers => deleted_files/usr/src/lib/libcmd/common/mapfile-vers
rename : usr/src/lib/libcmd/common/placeholder.c => deleted_files/usr/src/lib/libcmd/common/placeholder.c

1 files changed, 2301 insertions, 0 deletions

diff --git a/usr/src/lib/libshell/common/sh/macro.c b/usr/src/lib/libshell/common/sh/macro.c
new file mode 100644
index 0000000000..8108050b14
--- /dev/null
+++ b/usr/src/lib/libshell/common/sh/macro.c
@@ -0,0 +1,2301 @@
+/***********************************************************************
+*                                                                      *
+*               This software is part of the ast package               *
+*           Copyright (c) 1982-2007 AT&T Knowledge Ventures            *
+*                      and is licensed under the                       *
+*                  Common Public License, Version 1.0                  *
+*                      by AT&T Knowledge Ventures                      *
+*                                                                      *
+*                A copy of the License is available at                 *
+*            http://www.opensource.org/licenses/cpl1.0.txt             *
+*         (with md5 checksum 059e8cd6165cb4c31e351f2b69388fd9)         *
+*                                                                      *
+*              Information and Software Systems Research               *
+*                            AT&T Research                             *
+*                           Florham Park NJ                            *
+*                                                                      *
+*                  David Korn <dgk@research.att.com>                   *
+*                                                                      *
+***********************************************************************/
+#pragma prototyped
+/*
+ * Shell macro expander
+ * expands ~
+ * expands ${...}
+ * expands $(...)
+ * expands $((...))
+ * expands `...`
+ *
+ *   David Korn
+ *   AT&T Labs
+ *
+ */
+
+#include	"defs.h"
+#include	<fcin.h>
+#include	<pwd.h>
+#include	"name.h"
+#include	"variables.h"
+#include	"shlex.h"
+#include	"io.h"
+#include	"shnodes.h"
+#include	"path.h"
+#include	"national.h"
+#include	"streval.h"
+
+#undef STR_GROUP
+#ifndef STR_GROUP
+#   define STR_GROUP	0
+#endif
+
+#if !SHOPT_MULTIBYTE
+#define mbchar(p)       (*(unsigned char*)p++)
+#endif
+
+static int	_c_;
+typedef struct  _mac_
+{
+	Shell_t		*shp;		/* pointer to shell interpreter */
+	Sfio_t		*sp;		/* stream pointer for here-document */
+	struct argnod	**arghead;	/* address of head of argument list */
+	char		*ifsp;		/* pointer to IFS value */
+	int		fields;		/* number of fields */
+	short		quoted;		/* set when word has quotes */
+	unsigned char	ifs;		/* first char of IFS */
+	char		quote;		/* set within double quoted contexts */
+	char		lit;		/* set within single quotes */
+	char		split;		/* set when word splittin is possible */
+	char		pattern;	/* set when file expansion follows */
+	char		patfound;	/* set if pattern character found */
+	char		assign;		/* set for assignments */
+	char		arith;		/* set for ((...)) */
+	char		let;		/* set when expanding let arguments */
+	char		zeros;		/* strip leading zeros when set */
+	void		*nvwalk;	/* for name space walking*/
+} Mac_t;
+
+#define mac	(*((Mac_t*)(sh.mac_context)))
+
+#undef ESCAPE
+#define ESCAPE		'\\'
+#define isescchar(s)	((s)>S_QUOTE)
+#define isqescchar(s)	((s)>=S_QUOTE)
+#define isbracechar(c)	((c)==RBRACE || (_c_=sh_lexstates[ST_BRACE][c])==S_MOD1 ||_c_==S_MOD2)
+#define ltos(x)		fmtbase((long)(x),0,0)
+
+/* type of macro expansions */
+#define M_BRACE		1	/* ${var}	*/
+#define M_TREE		2	/* ${var.}	*/
+#define M_SIZE		3	/* ${#var}	*/
+#define M_VNAME		4	/* ${!var}	*/
+#define M_SUBNAME	5	/* ${!var[sub]}	*/
+#define M_NAMESCAN	6	/* ${!var*}	*/
+#define M_NAMECOUNT	7	/* ${#var*}	*/
+#define M_TYPE		8	/* ${@var}	*/
+
+static int	substring(const char*, const char*, int[], int);
+static void	copyto(Mac_t*, int, int);
+static void	comsubst(Mac_t*,int);
+static int	varsub(Mac_t*);
+static void	mac_copy(Mac_t*,const char*, int);
+static void	tilde_expand2(int);
+static char 	*sh_tilde(const char*);
+static char	*special(int);
+static void	endfield(Mac_t*,int);
+static void	mac_error(Namval_t*);
+static char	*mac_getstring(char*);
+static int	charlen(const char*,int);
+#if SHOPT_MULTIBYTE
+    static char	*lastchar(const char*,const char*);
+#endif /* SHOPT_MULTIBYTE */
+
+void *sh_macopen(Shell_t *shp)
+{
+	void *addr = newof(0,Mac_t,1,0);
+	Mac_t *mp = (Mac_t*)addr;
+	mp->shp = shp;
+	return(addr);
+}
+
+/*
+ * perform only parameter substitution and catch failures
+ */
+char *sh_mactry(register char *string)
+{
+	if(string)
+	{
+		int		jmp_val;
+		int		savexit = sh.savexit;
+		struct checkpt	buff;
+		sh_pushcontext(&buff,SH_JMPSUB);
+		jmp_val = sigsetjmp(buff.buff,0);
+		if(jmp_val == 0)
+			string = sh_mactrim(string,0);
+		sh_popcontext(&buff);
+		sh.savexit = savexit;
+		return(string);
+	}
+	return("");
+}
+
+/*
+ * Perform parameter expansion, command substitution, and arithmetic
+ * expansion on <str>. 
+ * If <mode> greater than 1 file expansion is performed if the result 
+ * yields a single pathname.
+ * If <mode> negative, than expansion rules for assignment are applied.
+ */
+char *sh_mactrim(char *str, register int mode)
+{
+	register Mac_t *mp = (Mac_t*)sh.mac_context;
+	Mac_t	savemac;
+	savemac = *mp;
+	stakseek(0);
+	mp->arith = (mode==3);
+	mp->let = 0;
+	sh.argaddr = 0;
+	mp->pattern = (mode==1||mode==2);
+	mp->patfound = 0;
+	mp->assign = (mode<0);
+	mp->quoted = mp->lit = mp->split = mp->quote = 0;
+	mp->sp = 0;
+	if(mp->ifsp=nv_getval(nv_scoped(IFSNOD)))
+		mp->ifs = *mp->ifsp;
+	else
+		mp->ifs = ' ';
+	stakseek(0);
+	fcsopen(str);
+	copyto(mp,0,mp->arith);
+	str = stakfreeze(1);
+	if(mode==2)
+	{
+		/* expand only if unique */
+		struct argnod *arglist=0;
+		if((mode=path_expand(str,&arglist))==1)
+			str = arglist->argval;
+		else if(mode>1)
+			errormsg(SH_DICT,ERROR_exit(1),e_ambiguous,str);
+		sh_trim(str);
+	}
+	*mp = savemac;
+	return(str);
+}
+
+/*
+ * Perform all the expansions on the argument <argp>
+ */
+int sh_macexpand(register struct argnod *argp, struct argnod **arghead,int flag)
+{
+	register int flags = argp->argflag;
+	register char *str = argp->argval;
+	register Mac_t  *mp = (Mac_t*)sh.mac_context;
+	char **saveargaddr = sh.argaddr;
+	Mac_t savemac;
+	savemac = *mp;
+	mp->sp = 0;
+	if(mp->ifsp=nv_getval(nv_scoped(IFSNOD)))
+		mp->ifs = *mp->ifsp;
+	else
+		mp->ifs = ' ';
+	if(flag&ARG_OPTIMIZE)
+		sh.argaddr = (char**)&argp->argchn.ap;
+	else
+		sh.argaddr = 0;
+	mp->arghead = arghead;
+	mp->quoted = mp->lit = mp->quote = 0;
+	mp->arith = ((flag&ARG_ARITH)!=0);
+	mp->let = ((flag&ARG_LET)!=0);
+	mp->split = !(flag&ARG_ASSIGN);
+	mp->assign = !mp->split;
+	mp->pattern = mp->split && !(flag&ARG_NOGLOB) && !sh_isoption(SH_NOGLOB);
+	str = argp->argval;
+	fcsopen(str);
+	mp->fields = 0;
+	if(!arghead)
+	{
+		mp->split = 0;
+		mp->pattern = ((flag&ARG_EXP)!=0);
+		stakseek(0);
+	}
+	else
+	{
+		stakseek(ARGVAL);
+		*stakptr(ARGVAL-1) = 0;
+	}
+	mp->patfound = 0;
+	copyto(mp,0,mp->arith);
+	if(!arghead)
+	{
+		argp->argchn.cp = stakfreeze(1);
+		if(sh.argaddr)
+			argp->argflag |= ARG_MAKE;
+	}
+	else
+	{
+		endfield(mp,mp->quoted);
+		flags = mp->fields;
+		if(flags==1 && sh.argaddr)
+			argp->argchn.ap = *arghead; 
+	}
+	sh.argaddr = saveargaddr;
+	*mp = savemac;
+	return(flags);
+}
+
+/*
+ * Expand here document which is stored in <infile> or <string>
+ * The result is written to <outfile>
+ */
+void sh_machere(Sfio_t *infile, Sfio_t *outfile, char *string)
+{
+	register int	c,n;
+	register const char	*state = sh_lexstates[ST_QUOTE];
+	register char	*cp;
+	register Mac_t	*mp = (Mac_t*)sh.mac_context;
+	Fcin_t		save;
+	Mac_t		savemac;
+	savemac = *mp;
+	stakseek(0);
+	sh.argaddr = 0;
+	mp->sp = outfile;
+	mp->split = mp->assign = mp->pattern = mp->patfound = mp->lit = mp->arith = mp->let = 0;
+	mp->quote = 1;
+	mp->ifsp = nv_getval(nv_scoped(IFSNOD));
+	mp->ifs = ' ';
+	fcsave(&save);
+	if(infile)
+		fcfopen(infile);
+	else
+		fcsopen(string);
+	fcnotify(0);
+	cp = fcseek(0);
+	while(1)
+	{
+#if SHOPT_MULTIBYTE
+		if(mbwide())
+		{
+			do
+			{
+				ssize_t len;
+				switch(len = mbsize(cp))
+				{
+				    case -1:	/* illegal multi-byte char */
+				    case 0:
+				    case 1:
+					n=state[*(unsigned char*)cp++];
+					break;
+				    default:
+					/* use state of alpah character */
+					n=state['a'];
+					cp += len;
+				}
+			}
+			while(n == 0);
+		}
+		else
+#endif /* SHOPT_MULTIBYTE */
+		while((n=state[*(unsigned char*)cp++])==0);
+		if(n==S_NL || n==S_QUOTE || n==S_RBRA)
+			continue;
+		if(c=(cp-1)-fcseek(0))
+			sfwrite(outfile,fcseek(0),c);
+		cp = fcseek(c+1);
+		switch(n)
+		{
+		    case S_EOF:
+			if((n=fcfill()) <=0)
+			{
+				/* ignore 0 byte when reading from file */
+				if(n==0 && fcfile())
+					continue;
+				fcrestore(&save);
+				*mp = savemac;
+				return;
+			}
+			cp = fcseek(-1);
+			continue;
+		    case S_ESC:
+			fcgetc(c);
+			cp=fcseek(-1);
+			if(c>0)
+				cp++;
+			if(!isescchar(state[c]))
+				sfputc(outfile,ESCAPE);
+			continue;
+		    case S_GRAVE:
+			comsubst(mp,0);
+			break;
+		    case S_DOL:
+			c = fcget();
+			if(c=='.')
+				goto regular;
+		    again:
+			switch(n=sh_lexstates[ST_DOL][c])
+			{
+			    case S_ALP: case S_SPC1: case S_SPC2:
+			    case S_DIG: case S_LBRA:
+			    {
+				Fcin_t	save2;
+				int	offset = staktell();
+				int	offset2;
+				stakputc(c);
+				if(n==S_LBRA)
+					sh_lexskip(RBRACE,1,ST_BRACE);
+				else if(n==S_ALP)
+				{
+					while(fcgetc(c),isaname(c))
+						stakputc(c);
+					fcseek(-1);
+				}
+				stakputc(0);
+				offset2 = staktell();
+				fcsave(&save2);
+				fcsopen(stakptr(offset));
+				varsub(mp);
+				if(c=staktell()-offset2)
+					sfwrite(outfile,(char*)stakptr(offset2),c);
+				fcrestore(&save2);
+				stakseek(offset);
+				break;
+			    }
+			    case S_PAR:
+				comsubst(mp,1);
+				break;
+			    case S_EOF:
+				if((c=fcfill()) > 0)
+					goto again;
+				/* FALL THRU */
+			    default:
+			    regular:
+				sfputc(outfile,'$');
+				fcseek(-1);
+				break;
+			}
+		}
+		cp = fcseek(0);
+	}
+}
+
+/*
+ * expand argument but do not trim pattern characters
+ */
+char *sh_macpat(register struct argnod *arg, int flags)
+{
+	register char *sp = arg->argval;
+	if((arg->argflag&ARG_RAW))
+		return(sp);
+	if(flags&ARG_OPTIMIZE)
+		arg->argchn.ap=0;
+	if(!(sp=arg->argchn.cp))
+	{
+		sh_macexpand(arg,NIL(struct argnod**),flags);
+		sp = arg->argchn.cp;
+		if(!(flags&ARG_OPTIMIZE) || !(arg->argflag&ARG_MAKE))
+			arg->argchn.cp = 0;
+		arg->argflag &= ~ARG_MAKE;
+	}
+	else
+		sh.optcount++;
+	return(sp);
+}
+
+/*
+ * Process the characters up to <endch> or end of input string 
+ */
+static void copyto(register Mac_t *mp,int endch, int newquote)
+{
+	register int	c,n;
+	register const char	*state = sh_lexstates[ST_MACRO];
+	register char	*cp,*first;
+	int		tilde = -1;
+	int		oldquote = mp->quote;
+	int		ansi_c = 0;
+	int		paren = 0;
+	int		ere = 0;
+	int		brace = 0;
+	Sfio_t		*sp = mp->sp;
+	mp->sp = NIL(Sfio_t*);
+	mp->quote = newquote;
+	first = cp = fcseek(0);
+	if(!mp->quote && *cp=='~')
+		tilde = staktell();
+	/* handle // operator specially */
+	if(mp->pattern==2 && *cp=='/')
+		cp++;
+	while(1)
+	{
+#if SHOPT_MULTIBYTE
+		if(mbwide())
+		{
+			ssize_t len;
+			do
+			{
+				switch(len = mbsize(cp))
+				{
+				    case -1:	/* illegal multi-byte char */
+				    case 0:
+					len = 1;
+				    case 1:
+					n = state[*(unsigned char*)cp++];
+					break;
+				    default:
+					/* treat as if alpha */
+					cp += len;
+					n=state['a'];
+				}
+			}
+			while(n == 0);
+			c = (cp-len) - first;
+		}
+		else
+#endif /* SHOPT_MULTIBYTE */
+		{
+			while((n=state[*(unsigned char*)cp++])==0);
+			c = (cp-1) - first;
+		}
+		switch(n)
+		{
+		    case S_ESC:
+			if(ansi_c)
+			{
+				/* process ANSI-C escape character */
+				char *addr= --cp;
+				if(c)
+					stakwrite(first,c);
+				c = chresc(cp,&addr);
+				cp = addr;
+				first = fcseek(cp-first);
+#if SHOPT_MULTIBYTE
+				if(c > UCHAR_MAX && mbwide())
+				{
+					int		i;
+					unsigned char	mb[8];
+
+					n = wctomb((char*)mb, c);
+					for(i=0;i<n;i++)
+						stakputc(mb[i]);
+				}
+				else
+#endif /* SHOPT_MULTIBYTE */
+				stakputc(c);
+				if(c==ESCAPE && mp->pattern)
+					stakputc(ESCAPE);
+				break;
+			}
+			else if(sh_isoption(SH_BRACEEXPAND) && mp->pattern==4 && (*cp==',' || *cp==LBRACE || *cp==RBRACE || *cp=='.'))
+				break;
+			else if(mp->split && endch && !mp->quote && !mp->lit)
+			{
+				if(c)
+					mac_copy(mp,first,c);
+				cp = fcseek(c+2);
+				if(c= cp[-1])
+				{
+					stakputc(c);
+					if(c==ESCAPE)
+						stakputc(ESCAPE);
+				}
+				else
+					cp--;
+				first = cp;
+				break;
+			}
+			n = state[*(unsigned char*)cp];
+			if(n==S_ENDCH && *cp!=endch)
+				n = S_PAT;
+			if(mp->pattern)
+			{
+				/* preserve \digit for pattern matching */
+				/* also \alpha for extended patterns */
+				if(!mp->lit && !mp->quote && (n==S_DIG || ((paren+ere) && sh_lexstates[ST_DOL][*(unsigned char*)cp]==S_ALP)))
+					break;
+				/* followed by file expansion */
+				if(!mp->lit && (n==S_ESC || (!mp->quote && 
+					(n==S_PAT||n==S_ENDCH||n==S_SLASH||n==S_BRACT||*cp=='-'))))
+				{
+					cp += (n!=S_EOF);
+					break;
+				}
+				if(mp->lit || (mp->quote && !isqescchar(n) && n!=S_ENDCH))
+				{
+					/* add \ for file expansion */
+					stakwrite(first,c+1);
+					first = fcseek(c);
+					break;
+				}
+			}
+			if(mp->lit)
+				break;
+			if(!mp->quote || isqescchar(n) || n==S_ENDCH)
+			{
+				/* eliminate \ */
+				if(c)
+					stakwrite(first,c);
+				/* check new-line joining */
+				first = fcseek(c+1);
+			}
+			cp += (n!=S_EOF);
+			break;
+		    case S_GRAVE: case S_DOL:
+			if(mp->lit)
+				break;
+			if(c)
+			{
+				if(mp->split && !mp->quote && endch)
+					mac_copy(mp,first,c);
+				else
+					stakwrite(first,c);
+			}
+			first = fcseek(c+1);
+			c = mp->pattern;
+			if(n==S_GRAVE)
+				comsubst(mp,0);
+			else if((n= *cp)==0 || !varsub(mp))
+			{
+				if(n=='\'' && !mp->quote)
+					ansi_c = 1;
+				else if(mp->quote || n!='"')
+					stakputc('$');
+			}
+			cp = first = fcseek(0);
+			if(*cp)
+				mp->pattern = c;
+			break;
+		    case S_ENDCH:
+			if((mp->lit || cp[-1]!=endch || mp->quote!=newquote))
+				goto pattern;
+			if(endch==RBRACE && *cp==LPAREN && mp->pattern && brace)
+				goto pattern;
+		    case S_EOF:
+			if(c)
+			{
+				if(mp->split && !mp->quote && !mp->lit && endch)
+					mac_copy(mp,first,c);
+				else
+					stakwrite(first,c);
+			}
+			c += (n!=S_EOF);
+			first = fcseek(c);
+			if(tilde>=0)
+				tilde_expand2(tilde);
+			goto done;
+		    case S_QUOTE:
+			if(mp->lit || mp->arith)
+				break;
+		    case S_LIT:
+			if(mp->arith)
+			{
+				if((*cp=='`' || *cp=='[') && cp[1]=='\'')
+					cp +=2;
+				break;
+			}
+			if(n==S_LIT && mp->quote)
+				break;
+			if(c)
+			{
+				if(mp->split && endch && !mp->quote && !mp->lit)
+					mac_copy(mp,first,c);
+				else
+					stakwrite(first,c);
+			}
+			first = fcseek(c+1);
+			if(n==S_LIT)
+			{
+				if(mp->quote)
+					continue;
+				if(mp->lit)
+					mp->lit = ansi_c = 0;
+				else
+					mp->lit = 1;
+			}
+			else
+				mp->quote = !mp->quote;
+			mp->quoted++;
+			break;
+		    case S_BRACT:
+			if(mp->arith || ((mp->assign==1 || endch==RBRACT) &&
+				!(mp->quote || mp->lit)))
+			{
+				int offset=0,oldpat = mp->pattern;
+				int oldarith = mp->arith;
+				stakwrite(first,++c);
+				if(mp->assign==1 && first[c-2]=='.')
+					offset = staktell();
+				first = fcseek(c);
+				mp->pattern = 4;
+				mp->arith = 0;
+				copyto(mp,RBRACT,0);
+				mp->arith = oldarith;
+				mp->pattern = oldpat;
+				stakputc(RBRACT);
+				if(offset)
+				{
+					cp = stakptr(staktell());
+					if(sh_checkid(stakptr(offset),cp)!=cp)
+						stakseek(staktell()-2);
+				}
+				cp = first = fcseek(0);
+				break;
+			}
+		    case S_PAT:
+			if(mp->pattern && !(mp->quote || mp->lit))
+			{
+				mp->patfound = mp->pattern;
+				if((n=cp[-1])==LPAREN)
+				{
+					paren++;
+					if((cp-first)>1 && cp[-2]=='~')
+					{
+						char *p = cp;
+						while((c=mbchar(p)) && c!=RPAREN && c!='E');
+						ere = c=='E';
+					}
+				}
+				else if(n==RPAREN)
+					--paren;
+			}
+			goto pattern;
+		    case S_BRACE:
+			if(!(mp->quote || mp->lit))
+			{
+				mp->patfound = mp->split && sh_isoption(SH_BRACEEXPAND);
+				brace = 1;
+			}
+		    pattern:
+			if(!mp->pattern || !(mp->quote || mp->lit))
+			{
+				/* mark beginning of {a,b} */
+				if(n==S_BRACE && endch==0 && mp->pattern)
+					mp->pattern=4;
+				if(n==S_SLASH && mp->pattern==2)
+					mp->pattern=3;
+				break;
+			}
+			if(mp->pattern==3)
+				break;
+			if(c)
+				stakwrite(first,c);
+			first = fcseek(c);
+			stakputc(ESCAPE);
+			break;
+		    case S_EQ:
+			if(mp->assign==1)
+			{
+				if(*cp=='~' && !endch && !mp->quote && !mp->lit)
+					tilde = staktell()+(c+1);
+				mp->assign = 2;
+			}
+			break;
+		    case S_SLASH:
+		    case S_COLON:
+			if(tilde >=0)
+			{
+				if(c)
+					stakwrite(first,c);
+				first = fcseek(c);
+				tilde_expand2(tilde);
+				tilde = -1;
+				c=0;
+			}
+			if(n==S_COLON && mp->assign==2 && *cp=='~' && endch==0 && !mp->quote &&!mp->lit)
+				tilde = staktell()+(c+1);
+			else if(n==S_SLASH && mp->pattern==2)
+#if 0
+				goto pattern;
+#else
+			{
+				if(mp->quote || mp->lit)
+					goto pattern;
+				stakwrite(first,c+1);
+				first = fcseek(c+1);
+				c = staktell();
+				sh_lexskip(RBRACE,0,ST_NESTED);
+				stakseek(c);
+				cp = fcseek(-1);
+				stakwrite(first,cp-first);
+				first=cp;
+			}
+#endif
+			break;
+		}
+	}
+done:
+	mp->sp = sp;
+	mp->quote = oldquote;
+}
+
+/*
+ * copy <str> to stack performing sub-expression substitutions
+ */
+static void mac_substitute(Mac_t *mp, register char *cp,char *str,register int subexp[],int subsize)
+{
+	register int c,n;
+#if 0
+	register char *first=cp;
+#else
+	register char *first=fcseek(0);
+	char *ptr;
+	Mac_t savemac;
+	n = staktell();
+	savemac = *mp;
+	mp->pattern = 3;
+	mp->split = 0;
+	fcsopen(cp);
+	copyto(mp,0,0);
+	stakputc(0);
+	ptr = cp = strdup(stakptr(n));
+	stakseek(n);
+	*mp = savemac;
+	fcsopen(first);
+	first = cp;
+#endif
+	while(1)
+	{
+		while((c= *cp++) && c!=ESCAPE);
+		if(c==0)
+			break;
+		if((n= *cp++)=='\\' || n==RBRACE || (n>='0' && n<='9' && (n-='0')<subsize))
+		{
+			c = cp-first-2;
+			if(c)
+				mac_copy(mp,first,c);
+			first=cp;
+			if(n=='\\' || n==RBRACE)
+			{
+				first--;
+				continue;
+			}
+			if((c=subexp[2*n])>=0)
+			{
+				if((n=subexp[2*n+1]-c)>0)
+					mac_copy(mp,str+c,n);
+			}
+		}
+		else if(n==0)
+			break;
+	}
+	if(n=cp-first-1)
+		mac_copy(mp,first,n);
+#if 1
+	free(ptr);
+#endif
+}
+
+#if  SHOPT_FILESCAN
+#define	MAX_OFFSETS	 (sizeof(shp->offsets)/sizeof(shp->offsets[0]))
+#define MAX_ARGN	(32*1024)
+
+/*
+ * compute the arguments $1 ... $n and $# from the current line as needed
+ * save line offsets in the offsets array.
+ */
+static char *getdolarg(Shell_t *shp, int n, int *size)
+{
+	register int c=S_DELIM, d=shp->ifstable['\\'];
+	register unsigned char *first,*last,*cp = (unsigned char*)shp->cur_line;
+	register int m=shp->offsets[0],delim=0;
+	if(m==0)
+		return(0);
+	if(m<0)
+		m = 0;
+	else if(n<=m)
+		m = n-1;
+	else
+		m--;
+	if(m >= MAX_OFFSETS-1)
+		m =  MAX_OFFSETS-2;
+	cp += shp->offsets[m+1];
+	n -= m;
+	shp->ifstable['\\'] = 0;
+	shp->ifstable[0] = S_EOF;
+	while(1)
+	{
+		if(c==S_DELIM)
+			while(shp->ifstable[*cp++]==S_SPACE);
+		first = --cp;
+		if(++m < MAX_OFFSETS)
+			shp->offsets[m] = (first-(unsigned char*)shp->cur_line);
+		while((c=shp->ifstable[*cp++])==0);
+		last = cp-1;
+		if(c==S_SPACE)
+			while((c=shp->ifstable[*cp++])==S_SPACE);
+		if(--n==0 || c==S_EOF)
+		{
+			if(last==first && c==S_EOF && (!delim || (m>1)))
+			{
+				n++;
+				m--;
+			}
+			break;
+		}
+		delim = (c==S_DELIM);
+	}
+	shp->ifstable['\\'] = d;
+	if(m > shp->offsets[0])
+		shp->offsets[0] = m;
+	if(n)
+		first = last = 0;
+	if(size)
+		*size = last-first;
+	return((char*)first);
+}
+#endif /* SHOPT_FILESCAN */
+
+/*
+ * get the prefix after name reference resolution
+ */
+static char *prefix(char *id)
+{
+	Namval_t *np;
+	register char *cp = strchr(id,'.');
+	if(cp)
+	{
+		*cp = 0;
+		np = nv_search(id, sh.var_tree,0);
+		*cp = '.';
+		if(isastchar(cp[1]))
+			cp[1] = 0;
+		if(np && nv_isref(np))
+		{
+			int n;
+			char *sp;
+			sh.argaddr = 0;
+			while(nv_isref(np))
+				np = nv_refnode(np);
+			id = (char*)malloc(strlen(cp)+1+(n=strlen(sp=nv_name(np)))+1);
+			strcpy(&id[n],cp);
+			memcpy(id,sp,n);
+			return(id);
+		}
+	}
+	return(strdup(id));
+}
+
+/*
+ * copy to ']' onto the stack and return offset to it
+ */
+static int subcopy(Mac_t *mp, int flag)
+{
+	int split = mp->split;
+	int xpattern = mp->pattern;
+	int loc = staktell();
+	int xarith = mp->arith;
+	mp->split = 0;
+	mp->arith = 0;
+	mp->pattern = flag?4:0;
+	copyto(mp,RBRACT,0);
+	mp->pattern = xpattern;
+	mp->split = split;
+	mp->arith = xarith;
+	return(loc);
+}
+
+static int namecount(Mac_t *mp,const char *prefix)
+{
+	int count = 0;
+	mp->nvwalk = nv_diropen(prefix);
+	while(nv_dirnext(mp->nvwalk))
+		count++;
+	nv_dirclose(mp->nvwalk);
+	return(count);
+}
+
+static char *nextname(Mac_t *mp,const char *prefix, int len)
+{
+	char *cp;
+	if(len==0)
+	{
+		mp->nvwalk = nv_diropen(prefix);
+		return((char*)mp->nvwalk);
+	}
+	if(!(cp=nv_dirnext(mp->nvwalk)))
+		nv_dirclose(mp->nvwalk);
+	return(cp);
+}
+
+/*
+ * This routine handles $param,  ${parm}, and ${param op word}
+ * The input stream is assumed to be a string
+ */
+static int varsub(Mac_t *mp)
+{
+	register int	c;
+	register int	type=0; /* M_xxx */
+	register char	*v,*argp=0;
+	register Namval_t	*np = NIL(Namval_t*);
+	register int 	dolg=0, mode=0;
+	Namarr_t	*ap=0;
+	int		dolmax=0, vsize= -1, offset= -1, nulflg, replen=0, bysub=0;
+	char		idbuff[3], *id = idbuff, *pattern=0, *repstr;
+	int		oldpat=mp->pattern,idnum=0,flag=0,d;
+retry1:
+	mp->zeros = 0;
+	idbuff[0] = 0;
+	idbuff[1] = 0;
+	c = fcget();
+	switch(c>0x7f?S_ALP:sh_lexstates[ST_DOL][c])
+	{
+	    case S_RBRA:
+		if(type<M_SIZE)
+			goto nosub;
+		/* This code handles ${#} */
+		c = mode;
+		mode = type = 0;
+		/* FALL THRU */
+	    case S_SPC1:
+		if(type==M_BRACE)
+		{
+			if(isaletter(mode=fcpeek(0)) || mode=='.')
+			{
+				if(c=='#')
+					type = M_SIZE;
+#ifdef SHOPT_TYPEDEF
+				else if(c=='@')
+				{
+					type = M_TYPE;
+					goto retry1;
+				}
+#endif /* SHOPT_TYPEDEF */
+				else
+					type = M_VNAME;
+				mode = c;
+				goto retry1;
+			}
+			else if(c=='#' && (isadigit(mode)||fcpeek(1)==RBRACE))
+			{
+				type = M_SIZE;
+				mode = c;
+				goto retry1;
+			}
+		}
+		/* FALL THRU */
+	    case S_SPC2:
+		*id = c;
+		v = special(c);
+		if(isastchar(c))
+		{
+			mode = c;
+#if  SHOPT_FILESCAN
+			if(sh.cur_line)
+			{
+				v = getdolarg(&sh,1,(int*)0);
+				dolmax = MAX_ARGN;
+			}
+			else
+#endif  /* SHOPT_FILESCAN */
+			dolmax = sh.st.dolc+1;
+			dolg = (v!=0);
+		}
+		break;
+	    case S_LBRA:
+		if(type)
+			goto nosub;
+		type = M_BRACE;
+		goto retry1;
+	    case S_PAR:
+		if(type)
+			goto nosub;
+		comsubst(mp,1);
+		return(1);
+	    case S_DIG:
+		c -= '0';
+		sh.argaddr = 0;
+		if(type)
+		{
+			register int d;
+			while((d=fcget()),isadigit(d))
+				c = 10*c + (d-'0');
+			fcseek(-1);
+		}
+		idnum = c;
+		if(c==0)
+			v = special(c);
+#if  SHOPT_FILESCAN
+		else if(sh.cur_line)
+		{
+			sh.used_pos = 1;
+			v = getdolarg(&sh,c,&vsize);
+		}
+#endif  /* SHOPT_FILESCAN */
+		else if(c <= sh.st.dolc)
+		{
+			sh.used_pos = 1;
+			v = sh.st.dolv[c];
+		}
+		else
+			v = 0;
+		break;
+	    case S_ALP:
+		if(c=='.' && type==0)
+			goto nosub;
+		offset = staktell();
+		do
+		{
+			np = 0;
+			do
+				stakputc(c);
+			while(((c=fcget()),(c>0x7f||isaname(c)))||type && c=='.');
+			while(c==LBRACT && type)
+			{
+				sh.argaddr=0;
+				if((c=fcget(),isastchar(c)) && fcpeek(0)==RBRACT)
+				{
+					if(type==M_VNAME)
+						type = M_SUBNAME;
+					idbuff[0] = mode = c;
+					fcget();
+					c = fcget();
+					if(c=='.' || c==LBRACT)
+					{
+						stakputc(LBRACT);
+						stakputc(mode);
+						stakputc(RBRACT);
+					}
+					else
+						flag = NV_ARRAY;
+					break;
+				}
+				else
+				{
+					fcseek(-1);
+					if(type==M_VNAME)
+						type = M_SUBNAME;
+					stakputc(LBRACT);
+					v = stakptr(subcopy(mp,1));
+					stakputc(RBRACT);
+					c = fcget();
+				}
+			}
+		}
+		while(type && c=='.');
+		if(c==RBRACE && type &&  fcpeek(-2)=='.')
+		{
+			stakseek(staktell()-1);
+			type = M_TREE;
+		}
+		stakputc(0);
+		id=stakptr(offset);
+		if(isastchar(c) && type)
+		{
+			if(type==M_VNAME || type==M_SIZE)
+			{
+				idbuff[0] = mode = c;
+				if((d=fcpeek(0))==c)
+					idbuff[1] = fcget();
+				if(type==M_VNAME)
+					type = M_NAMESCAN;
+				else
+					type = M_NAMECOUNT;
+				break;
+			}
+			goto nosub;
+		}
+		flag |= NV_NOASSIGN|NV_VARNAME|NV_NOADD;
+		if(c=='=' || c=='?' || (c==':' && ((d=fcpeek(0))=='=' || d=='?')))
+			flag &= ~NV_NOADD;
+#if  SHOPT_FILESCAN
+		if(sh.cur_line && *id=='R' && strcmp(id,"REPLY")==0)
+		{
+			sh.argaddr=0;
+			np = REPLYNOD;
+		}
+		else
+#endif  /* SHOPT_FILESCAN */
+		if(sh.argaddr)
+			flag &= ~NV_NOADD;
+		np = nv_open(id,sh.var_tree,flag|NV_NOFAIL);
+		ap = np?nv_arrayptr(np):0;
+		if(type)
+		{
+			if(ap && isastchar(mode) && !(ap->nelem&ARRAY_SCAN))
+				nv_putsub(np,NIL(char*),ARRAY_SCAN);
+			if(!isbracechar(c))
+				goto nosub;
+			else
+				fcseek(-1);
+		}
+		else
+			fcseek(-1);
+		if((type==M_VNAME||type==M_SUBNAME)  && sh.argaddr && strcmp(nv_name(np),id))
+			sh.argaddr = 0;
+		c = (type>M_BRACE && isastchar(mode));
+		if(np && (!c || !ap))
+		{
+			if(type==M_VNAME)
+			{
+				type = M_BRACE;
+				v = nv_name(np);
+			}
+#ifdef SHOPT_TYPEDEF
+			else if(type==M_TYPE)
+			{
+#if 0
+				Namval_t *nq = nv_type(np);
+#else
+				Namval_t *nq = 0;
+#endif
+				type = M_BRACE;
+				if(nq)
+					v = nv_name(nq);
+				else
+				{
+					nv_attribute(np,sh.strbuf,"typeset",1);
+					v = sfstruse(sh.strbuf);
+				}
+			}
+#endif /* SHOPT_TYPEDEF */
+#if  SHOPT_FILESCAN
+			else if(sh.cur_line && np==REPLYNOD)
+				v = sh.cur_line;
+#endif  /* SHOPT_FILESCAN */
+			else if(type==M_TREE)
+				v = nv_getvtree(np,(Namfun_t*)0);
+			else
+			{
+				v = nv_getval(np);
+				/* special case --- ignore leading zeros */  
+				if( (mp->arith||mp->let) && (np->nvfun || nv_isattr(np,(NV_LJUST|NV_RJUST|NV_ZFILL))) && (offset==0 || !isalnum(*((unsigned char*)stakptr(offset-1)))))
+					mp->zeros = 1;
+			}
+		}
+		else
+			v = 0;
+		stakseek(offset);
+		if(ap)
+		{
+#if SHOPT_OPTIMIZE
+			if(sh.argaddr)
+				nv_optimize(np);
+#endif
+			if(isastchar(mode) && array_elem(ap)> !c)
+				dolg = -1;
+			else
+				dolg = 0;
+		}
+		break;
+	    case S_EOF:
+		fcseek(-1);
+	    default:
+		goto nosub;
+	}
+	c = fcget();
+	if(type>M_TREE)
+	{
+		if(c!=RBRACE)
+			mac_error(np);
+		if(type==M_NAMESCAN || type==M_NAMECOUNT)
+		{
+			id = prefix(id);
+			stakseek(offset);
+			if(type==M_NAMECOUNT)
+			{
+				c = namecount(mp,id);
+				v = ltos(c);
+			}
+			else
+			{
+				dolmax = strlen(id);
+				dolg = -1;
+				nextname(mp,id,0);
+				v = nextname(mp,id,dolmax);
+			}
+		}
+		else if(type==M_SUBNAME)
+		{
+			if(dolg<0)
+			{
+				v = nv_getsub(np);
+				bysub=1;
+			}
+			else if(v)
+			{
+				if(!ap || isastchar(mode))
+					v = "0";
+				else
+					v = nv_getsub(np);
+			}
+		}
+		else
+		{
+			if(!isastchar(mode))
+				c = charlen(v,vsize);
+			else if(dolg>0)
+			{
+#if  SHOPT_FILESCAN
+				if(sh.cur_line)
+				{
+					getdolarg(&sh,MAX_ARGN,(int*)0);
+					c = sh.offsets[0];
+				}
+				else
+#endif  /* SHOPT_FILESCAN */
+				c = sh.st.dolc;
+			}
+			else if(dolg<0)
+				c = array_elem(ap);
+			else
+				c = (v!=0);
+			dolg = dolmax = 0;
+			v = ltos(c);
+		}
+		c = RBRACE;
+	}
+	nulflg = 0;
+	if(type && c==':')
+	{
+		c = fcget();
+		if(sh_lexstates[ST_BRACE][c]==S_MOD1 && c!='*' && c!= ':')
+			nulflg=1;
+		else if(c!='%' && c!='#')
+		{
+			fcseek(-1);
+			c = ':';
+		}
+	}
+	if(type)
+	{
+		if(!isbracechar(c))
+		{
+			if(!nulflg)
+				mac_error(np);
+			fcseek(-1);
+			c = ':';
+		}
+		if(c!=RBRACE)
+		{
+			int newops = (c=='#' || c == '%' || c=='/');
+			offset = staktell();
+			if(c=='/' ||c==':' || ((!v || (nulflg && *v==0)) ^ (c=='+'||c=='#'||c=='%')))
+			{
+				int newquote = mp->quote;
+				int split = mp->split;
+				int quoted = mp->quoted;
+				int arith = mp->arith;
+				int zeros = mp->zeros;
+				if(newops)
+				{
+					type = fcget();
+					if(type=='%' || type=='#')
+					{
+						int d = fcget();
+						fcseek(-1);
+						if(d=='(')
+							type = 0;
+					}
+					fcseek(-1);
+					mp->pattern = 1+(c=='/');
+					mp->split = 0;
+					mp->quoted = 0;
+					mp->arith = mp->zeros = 0;
+					newquote = 0;
+				}
+				else if(c=='?' || c=='=')
+					mp->split = mp->pattern = 0;
+				copyto(mp,RBRACE,newquote);
+				if(!oldpat)
+					mp->patfound = 0;
+				mp->pattern = oldpat;
+				mp->split = split;
+				mp->quoted = quoted;
+				mp->arith = arith;
+				mp->zeros = zeros;
+				/* add null byte */
+				stakputc(0);
+				stakseek(staktell()-1);
+			}
+			else
+			{
+				sh_lexskip(RBRACE,0,(!newops&&mp->quote)?ST_QUOTE:ST_NESTED);
+				stakseek(offset);
+			}
+			argp=stakptr(offset);
+		}
+	}
+	else
+	{
+		fcseek(-1);
+		c=0;
+	}
+	if(c==':')  /* ${name:expr1[:expr2]} */
+	{
+		char *ptr;
+		type = (int)sh_strnum(argp,&ptr,1);
+		if(isastchar(mode))
+		{
+			if(id==idbuff)  /* ${@} or ${*} */
+			{
+				if(type<0 && (type+= dolmax)<0)
+					type = 0;
+				if(type==0)
+					v = special(dolg=0);
+#if  SHOPT_FILESCAN
+				else if(sh.cur_line)
+				{
+					v = getdolarg(&sh,dolg=type,&vsize);
+					if(!v)
+						dolmax = type;
+				}
+#endif  /* SHOPT_FILESCAN */
+				else if(type < dolmax)
+					v = sh.st.dolv[dolg=type];
+				else
+					v =  0;
+			}
+			else if(ap)
+			{
+				if(type<0)
+				{
+					if(array_assoc(ap))
+						type = -type;
+					else
+						type += array_maxindex(np);
+				}
+				if(array_assoc(ap))
+				{
+					while(type-- >0 && (v=0,nv_nextsub(np)))
+						v = nv_getval(np);
+				}
+				else if(type > 0)
+				{
+					if(nv_putsub(np,NIL(char*),type|ARRAY_SCAN))
+						v = nv_getval(np);
+					else
+						v = 0;
+				}
+			}
+			else if(type>0)
+				v = 0;
+		}
+		else if(v)
+		{
+			vsize = charlen(v,vsize);
+			if(type<0 && (type += vsize)<0)
+				type = 0;
+			if(vsize < type)
+				v = 0;
+#if SHOPT_MULTIBYTE
+			else if(mbwide())
+			{
+				mbinit();
+				while(type-->0)
+				{
+					if((c=mbsize(v))<1)
+						c = 1;
+					v += c;
+				}
+				c = ':';
+			}
+#endif /* SHOPT_MULTIBYTE */
+			else
+				v += type;
+			vsize -= type;
+		}
+		if(*ptr==':')
+		{
+			if((type = (int)sh_strnum(ptr+1,&ptr,1)) <=0)
+				v = 0;
+			else if(isastchar(mode))
+			{
+				if(dolg>=0)
+				{
+					if(dolg+type < dolmax)
+						dolmax = dolg+type;
+				}
+				else
+					dolmax = type;
+			}
+			else if(type < vsize)
+			{
+#if SHOPT_MULTIBYTE
+				if(mbwide())
+				{
+					char *vp = v;
+					mbinit();
+					while(type-->0)
+					{
+						if((c=mbsize(vp))<1)
+							c = 1;
+						vp += c;
+					}
+					type = vp-v;
+					c = ':';
+				}
+#endif /* SHOPT_MULTIBYTE */
+				vsize = type;
+			}
+		}
+		if(*ptr)
+			mac_error(np);
+		stakseek(offset);
+		argp = 0;
+	}
+	/* check for substring operations */
+	else if(c == '#' || c == '%' || c=='/')
+	{
+		if(c=='/')
+		{
+			if(type=='/' || type=='#' || type=='%')
+			{
+				c = type;
+				type = '/';
+				argp++;
+			}
+			else
+				type = 0;
+		}
+		else
+		{
+			if(type==c) /* ## or %% */
+				argp++;
+			else
+				type = 0;
+		}
+		pattern = strdup(argp);
+		if((type=='/' || c=='/') && (repstr = mac_getstring(pattern)))
+			replen = strlen(repstr);
+		if(v || c=='/' && offset>=0)
+			stakseek(offset);
+	}
+	/* check for quoted @ */
+	if(mode=='@' && mp->quote && !v && c!='-')
+		mp->quoted-=2;
+retry2:
+	if(v && (!nulflg || *v ) && c!='+')
+	{
+		register int d = (mode=='@'?' ':mp->ifs);
+		int match[2*(MATCH_MAX+1)], nmatch, vsize_last;
+		char *vlast;
+		while(1)
+		{
+			if(!v)
+				v= "";
+			if(c=='/' || c=='#' || c== '%')
+			{
+				flag = (type || c=='/')?STR_GROUP|STR_MAXIMAL:STR_GROUP;
+				if(c!='/')
+					flag |= STR_LEFT;
+				while(1)
+				{
+					vsize = strlen(v);
+					if(c=='%')
+						nmatch=substring(v,pattern,match,flag&STR_MAXIMAL);
+					else
+						nmatch=strgrpmatch(v,pattern,match,elementsof(match)/2,flag);
+					if(replen>0)
+						sh_setmatch(v,vsize,nmatch,match);
+					if(nmatch)
+					{
+						vlast = v;
+						vsize_last = vsize;
+						vsize = match[0];
+					}
+					else if(c=='#')
+						vsize = 0;
+					if(vsize)
+						mac_copy(mp,v,vsize);
+					if(nmatch && replen>0)
+						mac_substitute(mp,repstr,v,match,nmatch);
+					if(nmatch==0)
+						v += vsize;
+					else
+						v += match[1];
+					if(*v &&  c=='/' && type)
+					{
+						/* avoid infinite loop */
+						if(nmatch && match[1]==0)
+							v++;
+						continue;
+					}
+					vsize = -1;
+					break;
+				}
+				if(replen==0)
+					sh_setmatch(vlast,vsize_last,nmatch,match);
+			}
+			if(vsize)
+				mac_copy(mp,v,vsize>0?vsize:strlen(v));
+			if(dolg==0 && dolmax==0)
+				 break;
+			if(dolg>=0)
+			{
+				if(++dolg >= dolmax)
+					break;
+#if  SHOPT_FILESCAN
+				if(sh.cur_line)
+				{
+					if(dolmax==MAX_ARGN && isastchar(mode))
+						break;
+					if(!(v=getdolarg(&sh,dolg,&vsize)))
+					{
+						dolmax = dolg;
+						break;
+					}
+				}
+				else
+#endif  /* SHOPT_FILESCAN */
+				v = sh.st.dolv[dolg];
+			}
+			else if(!np)
+			{
+				if(!(v = nextname(mp,id,dolmax)))
+					break;
+			}
+			else
+			{
+				if(dolmax &&  --dolmax <=0)
+				{
+					nv_putsub(np,NIL(char*),ARRAY_UNDEF);
+					break;
+				}
+				if(nv_nextsub(np) == 0)
+					break;
+				if(bysub)
+					v = nv_getsub(np);
+				else
+					v = nv_getval(np);
+			}
+			if(mp->split && (!mp->quote || mode=='@'))
+			{
+				if(!np)
+					mp->pattern = 0;
+				endfield(mp,mp->quoted);
+				mp->pattern = oldpat;
+			}
+			else if(d)
+			{
+				if(mp->sp)
+					sfputc(mp->sp,d);
+				else
+					stakputc(d);
+			}
+		}
+		if(pattern)
+			free((void*)pattern);
+	}
+	else if(argp)
+	{
+		if(c=='/' && replen>0 && pattern && strmatch("",pattern))
+			mac_substitute(mp,repstr,v,0,0);
+		if(c=='?')
+		{
+			if(np)
+				id = nv_name(np);
+			else if(idnum)
+				id = ltos(idnum);
+			if(*argp)
+			{
+				stakputc(0);
+				errormsg(SH_DICT,ERROR_exit(1),"%s: %s",id,argp);
+			}
+			else if(v)
+				errormsg(SH_DICT,ERROR_exit(1),e_nullset,id);
+			else
+				errormsg(SH_DICT,ERROR_exit(1),e_notset,id);
+		}
+		else if(c=='=')
+		{
+			if(np)
+			{
+				if(sh.subshell)
+					np = sh_assignok(np,1);
+				nv_putval(np,argp,0);
+				v = nv_getval(np);
+				nulflg = 0;
+				stakseek(offset);
+				goto retry2;
+			}
+		else
+			mac_error(np);
+		}
+	}
+	else if(sh_isoption(SH_NOUNSET) && (!np  || nv_isnull(np) || (nv_isarray(np) && !np->nvalue.cp)))
+	{
+		if(np)
+		{
+			if(nv_isarray(np))
+			{
+				sfprintf(sh.strbuf,"%s[%s]\0",nv_name(np),nv_getsub(np));
+				id = nv_getsub(np);
+				id = sfstruse(sh.strbuf);
+			}
+			else
+				id = nv_name(np);
+			nv_close(np);
+		}
+		errormsg(SH_DICT,ERROR_exit(1),e_notset,id);
+	}
+	if(np)
+		nv_close(np);
+	return(1);
+nosub:
+	if(type)
+		mac_error(np);
+	fcseek(-1);
+	nv_close(np);
+	return(0);
+}
+
+/*
+ * This routine handles command substitution
+ * <type> is 0 for older `...` version
+ */
+static void comsubst(Mac_t *mp,int type)
+{
+	Sfdouble_t		num;
+	register int		c;
+	register char		*str;
+	Sfio_t			*sp;
+	Fcin_t			save;
+	struct slnod            *saveslp = sh.st.staklist;
+	struct _mac_		savemac;
+	int			savtop = staktell();
+	char			lastc, *savptr = stakfreeze(0);
+	int			was_history = sh_isstate(SH_HISTORY);
+	int			was_verbose = sh_isstate(SH_VERBOSE);
+	int			newlines,bufsize;
+	register Shnode_t	*t;
+	Namval_t		*np;
+	sh.argaddr = 0;
+	savemac = *mp;
+	sh.st.staklist=0;
+	if(type)
+	{
+		sp = 0;
+		fcseek(-1);
+		t = sh_dolparen();
+		if(t && t->tre.tretyp==TARITH)
+		{
+			str =  t->ar.arexpr->argval;
+			fcsave(&save);
+			if(!(t->ar.arexpr->argflag&ARG_RAW))
+				str = sh_mactrim(str,3);
+			num = sh_arith(str);
+		out_offset:
+			stakset(savptr,savtop);
+			*mp = savemac;
+			if((Sflong_t)num==num)
+				sfprintf(sh.strbuf,"%lld",(Sflong_t)num);
+			else
+				sfprintf(sh.strbuf,"%.*Lg",LDBL_DIG,num);
+			str = sfstruse(sh.strbuf);
+			mac_copy(mp,str,strlen(str));
+			sh.st.staklist = saveslp;
+			fcrestore(&save);
+			return;
+		}
+	}
+	else
+	{
+		while(fcgetc(c)!='`' && c)
+		{
+			if(c==ESCAPE)
+			{
+				fcgetc(c);
+				if(!(isescchar(sh_lexstates[ST_QUOTE][c]) ||
+				  (c=='"' && mp->quote)) || (c=='$' && fcpeek(0)=='\''))
+					stakputc(ESCAPE);
+			}
+			stakputc(c);
+		}
+		c = staktell();
+		str=stakfreeze(1);
+		/* disable verbose and don't save in history file */
+		sh_offstate(SH_HISTORY);
+		sh_offstate(SH_VERBOSE);
+		if(mp->sp)
+			sfsync(mp->sp);	/* flush before executing command */
+		sp = sfnew(NIL(Sfio_t*),str,c,-1,SF_STRING|SF_READ);
+		c = sh.inlineno;
+		sh.inlineno = error_info.line+sh.st.firstline;
+		t = (Shnode_t*)sh_parse(mp->shp, sp,SH_EOF|SH_NL);
+		sh.inlineno = c;
+	}
+#if KSHELL
+	if(t)
+	{
+		fcsave(&save);
+		sfclose(sp);
+		if(t->tre.tretyp==0 && !t->com.comarg)
+		{
+			/* special case $(<file) and $(<#file) */
+			register int fd;
+			int r;
+			struct checkpt buff;
+			struct ionod *ip=0;
+			sh_pushcontext(&buff,SH_JMPIO);
+			if((ip=t->tre.treio) && 
+				((ip->iofile&IOLSEEK) || !(ip->iofile&IOUFD)) &&
+				(r=sigsetjmp(buff.buff,0))==0)
+				fd = sh_redirect(ip,3);
+			else
+				fd = sh_chkopen(e_devnull);
+			sh_popcontext(&buff);
+			if(r==0 && ip && (ip->iofile&IOLSEEK))
+			{
+				if(sp=sh.sftable[fd])
+					num = sftell(sp);
+				else
+					num = lseek(fd, (off_t)0, SEEK_CUR);
+				goto out_offset;
+			}
+			sp = sfnew(NIL(Sfio_t*),(char*)malloc(IOBSIZE+1),IOBSIZE,fd,SF_READ|SF_MALLOC);
+		}
+		else
+			sp = sh_subshell(t,sh_isstate(SH_ERREXIT),1);
+		fcrestore(&save);
+	}
+	else
+		sp = sfopen(NIL(Sfio_t*),"","sr");
+	sh_freeup();
+	sh.st.staklist = saveslp;
+	if(was_history)
+		sh_onstate(SH_HISTORY);
+	if(was_verbose)
+		sh_onstate(SH_VERBOSE);
+#else
+	sp = sfpopen(NIL(Sfio_t*),str,"r");
+#endif
+	*mp = savemac;
+	np = nv_scoped(IFSNOD);
+	nv_putval(np,mp->ifsp,0);
+	mp->ifsp = nv_getval(np);
+	stakset(savptr,savtop);
+	newlines = 0;
+	lastc = 0;
+	sfsetbuf(sp,(void*)sp,0);
+	bufsize = sfvalue(sp);
+	/* read command substitution output and put on stack or here-doc */
+	sfpool(sp, NIL(Sfio_t*), SF_WRITE);
+	while((str=(char*)sfreserve(sp,SF_UNBOUND,0)) && (c = sfvalue(sp))>0)
+	{
+#if SHOPT_CRNL
+		/* eliminate <cr> */
+		register char *dp;
+		char *buff = str;
+		while(c>1 && (*str !='\r'|| str[1]!='\n'))
+		{
+			c--;
+			str++;
+		}
+		dp = str;
+		while(c>1)
+		{
+			str++;
+			c--;
+			while(c>1 && (*str!='\r' || str[1]!='\n'))
+			{
+				c--;
+				*dp++ = *str++;
+			}
+		}
+		if(c)
+			*dp++ = *str++;
+		*dp = 0;
+		str = buff;
+		c = dp-str;
+#endif /* SHOPT_CRNL */
+		if(newlines >0)
+		{
+			if(mp->sp)
+				sfnputc(mp->sp,'\n',newlines);
+			else if(!mp->quote && mp->split && sh.ifstable['\n'])
+				endfield(mp,0);
+			else	while(newlines--)
+					stakputc('\n');
+			newlines = 0;
+		}
+		else if(lastc)
+		{
+			mac_copy(mp,&lastc,1);
+			lastc = 0;
+		}
+		/* delay appending trailing new-lines */
+		while(str[--c]=='\n')
+			newlines++;
+		if(++c < bufsize)
+			str[c] = 0;
+		else
+		{
+			/* can't write past buffer so save last character */
+			lastc = str[--c];
+			str[c] = 0;
+		}
+		mac_copy(mp,str,c);
+	}
+	if(--newlines>0 && sh.ifstable['\n']==S_DELIM)
+	{
+		if(mp->sp)
+			sfnputc(mp->sp,'\n',newlines);
+		else if(!mp->quote && mp->split && sh.ifstable['\n'])
+			endfield(mp,0);
+		else	while(newlines--)
+				stakputc('\n');
+	}
+	if(lastc)
+		mac_copy(mp,&lastc,1);
+	sfclose(sp);
+	return;
+}
+
+/*
+ * copy <str> onto the stack
+ */
+static void mac_copy(register Mac_t *mp,register const char *str, register int size)
+{
+	register char		*state;
+	register const char	*cp=str;
+	register int		c,n,nopat;
+	nopat = (mp->quote||mp->assign==1||mp->arith);
+	if(mp->zeros)
+	{
+		/* prevent leading 0's from becomming octal constants */
+		while(size>1 && *str=='0')
+			str++,size--;
+		mp->zeros = 0;
+		cp = str;
+	}
+	if(mp->sp)
+		sfwrite(mp->sp,str,size);
+	else if(mp->pattern>=2 || (mp->pattern && nopat))
+	{
+		state = sh_lexstates[ST_MACRO];
+		/* insert \ before file expansion characters */
+		while(size-->0)
+		{
+			c = state[n= *(unsigned char*)cp++];
+			if(nopat&&(c==S_PAT||c==S_ESC||c==S_BRACT||c==S_ENDCH) && mp->pattern!=3)
+				c=1;
+			else if(mp->pattern==4 && (c==S_ESC||c==S_BRACT||c==S_ENDCH || isastchar(n)))
+				c=1;
+			else if(mp->pattern==2 && c==S_SLASH)
+				c=1;
+			else if(mp->pattern==3 && c==S_ESC && (state[*(unsigned char*)cp]==S_DIG||(*cp==ESCAPE)))
+			{
+				if(!(c=mp->quote))
+					cp++;
+			}
+			else
+				c=0;
+			if(c)
+			{
+				if(c = (cp-1) - str)
+					stakwrite(str,c);
+				stakputc(ESCAPE);
+				str = cp-1;
+			}
+		}
+		if(c = cp-str)
+			stakwrite(str,c);
+	}
+	else if(!mp->quote && mp->split && (mp->ifs||mp->pattern))
+	{
+		/* split words at ifs characters */
+		state = sh.ifstable;
+		if(mp->pattern)
+		{
+			char *sp = "&|()";
+			while(c = *sp++)
+			{
+				if(state[c]==0)
+					state[c] = S_EPAT;
+			}
+			sp = "*?[{";
+			while(c = *sp++)
+			{
+				if(state[c]==0)
+					state[c] = S_PAT;
+			}
+			if(state[ESCAPE]==0)
+				state[ESCAPE] = S_ESC;
+		}
+		while(size-->0)
+		{
+			if((n=state[c= *(unsigned char*)cp++])==S_ESC || n==S_EPAT)
+			{
+				/* don't allow extended patterns in this case */
+				mp->patfound = mp->pattern;
+				stakputc(ESCAPE);
+			}
+			else if(n==S_PAT)
+				mp->patfound = mp->pattern;
+			else if(n && mp->ifs)
+			{
+#if SHOPT_MULTIBYTE
+				if(n==S_MBYTE)
+				{
+					if(sh_strchr(mp->ifsp,cp-1)<0)
+						continue;
+					n = mbsize(cp-1) - 1;
+					if(n==-2)
+						n = 0;
+					cp += n;
+					size -= n;
+					n= S_DELIM;
+				}
+#endif /* SHOPT_MULTIBYTE */
+				if(n==S_SPACE || n==S_NL)
+				{
+					while(size>0 && ((n=state[c= *(unsigned char*)cp++])==S_SPACE||n==S_NL))
+						size--;
+#if SHOPT_MULTIBYTE
+					if(n==S_MBYTE && sh_strchr(mp->ifsp,cp-1)>=0)
+					{
+						n = mbsize(cp-1) - 1;
+						if(n==-2)
+							n = 0;
+						cp += n;
+						size -= n;
+						n=S_DELIM;
+					}
+					else
+#endif /* SHOPT_MULTIBYTE */
+					if(n==S_DELIM)
+						size--;
+				}
+				endfield(mp,n==S_DELIM||mp->quoted);
+				mp->patfound = 0;
+				if(n==S_DELIM)
+					while(size>0 && ((n=state[c= *(unsigned char*)cp++])==S_SPACE||n==S_NL))
+						size--;
+				if(size<=0)
+					break;
+				cp--;
+				continue;
+
+			}
+			stakputc(c);
+		}
+		if(mp->pattern)
+		{
+			cp = "&|()";
+			while(c = *cp++)
+			{
+				if(state[c]==S_EPAT)
+					state[c] = 0;
+			}
+			cp = "*?[{";
+			while(c = *cp++)
+			{
+				if(state[c]==S_PAT)
+					state[c] = 0;
+			}
+			if(sh.ifstable[ESCAPE]==S_ESC)
+				sh.ifstable[ESCAPE] = 0;
+		}
+	}
+	else
+		stakwrite(str,size);
+}
+
+/*
+ * Terminate field.
+ * If field is null count field if <split> is non-zero
+ * Do filename expansion of required
+ */
+static void endfield(register Mac_t *mp,int split)
+{
+	register struct argnod *argp;
+	register int count=0;
+	if(staktell() > ARGVAL || split)
+	{
+		argp = (struct argnod*)stakfreeze(1);
+		argp->argnxt.cp = 0;
+		argp->argflag = 0;
+		if(mp->patfound)
+		{
+			sh.argaddr = 0;
+#if SHOPT_BRACEPAT
+			count = path_generate(argp,mp->arghead);
+#else
+			count = path_expand(argp->argval,mp->arghead);
+#endif /* SHOPT_BRACEPAT */
+			if(count)
+				mp->fields += count;
+			else if(split)	/* pattern is null string */
+				*argp->argval = 0;
+			else	/* pattern expands to nothing */
+				count = -1;
+		}
+		if(count==0)
+		{
+			argp->argchn.ap = *mp->arghead;
+			*mp->arghead = argp;
+			mp->fields++;
+		}
+		if(count>=0)
+		{
+			(*mp->arghead)->argflag |= ARG_MAKE;
+			if(mp->assign || sh_isoption(SH_NOGLOB))
+				argp->argflag |= ARG_RAW|ARG_EXP;
+		}
+		stakseek(ARGVAL);
+	}
+	mp->quoted = mp->quote;
+}
+
+/*
+ * Finds the right substring of STRING using the expression PAT
+ * the longest substring is found when FLAG is set.
+ */
+static int substring(register const char *string,const char *pat,int match[], int flag)
+{
+	register const char *sp=string;
+	register int size,len,nmatch,n;
+	int smatch[2*(MATCH_MAX+1)];
+	if(flag)
+	{
+		if(n=strgrpmatch(sp,pat,smatch,elementsof(smatch)/2,STR_RIGHT|STR_MAXIMAL))
+		{
+			memcpy(match,smatch,n*2*sizeof(smatch[0]));
+			return(n);
+		}
+		return(0);
+	}
+	size = len = strlen(sp);
+	sp += size;
+	while(sp>=string)
+	{
+#if SHOPT_MULTIBYTE
+		if(mbwide())
+			sp = lastchar(string,sp);
+#endif /* SHOPT_MULTIBYTE */
+		if(n=strgrpmatch(sp,pat,smatch,elementsof(smatch)/2,STR_RIGHT|STR_LEFT|STR_MAXIMAL))
+		{
+			nmatch = n;
+			memcpy(match,smatch,n*2*sizeof(smatch[0]));
+			size = sp-string;
+			break;
+		}
+		sp--;
+	}
+	if(size==len)
+		return(0);
+	if(nmatch)
+	{
+		nmatch *=2;
+		while(--nmatch>=0)
+			match[nmatch] += size;
+	}
+	return(n);
+}
+
+#if SHOPT_MULTIBYTE
+	static char	*lastchar(const char *string, const char *endstring)
+	{
+		register char *str = (char*)string;
+		register int c;
+		mbinit();
+		while(*str)
+		{
+			if((c=mbsize(str))<0)
+				c = 1;
+			if(str+c > endstring)
+				break;
+			str += c;
+		}
+		return(str);
+	}
+#endif /* SHOPT_MULTIBYTE */
+static int	charlen(const char *string,int len)
+{
+	if(!string)
+		return(0);
+#if SHOPT_MULTIBYTE
+	if(mbwide())
+	{
+		register const char *str = string, *strmax=string+len;
+		register int n=0;
+		mbinit();
+		if(len>0)
+		{
+			while(str<strmax && mbchar(str))
+				n++;
+		}
+		else while(mbchar(str))
+			n++;
+		return(n);
+	}
+	else
+#endif /* SHOPT_MULTIBYTE */
+	{
+		if(len<0)
+			return(strlen(string));
+		return(len);
+	}
+}
+
+/*
+ * This is the default tilde discipline function
+ */
+static int sh_btilde(int argc, char *argv[], void *context)
+{
+	char *cp = sh_tilde(argv[1]);
+	NOT_USED(argc);
+	NOT_USED(context);
+	if(!cp)
+		cp = argv[1];
+	sfputr(sfstdout, cp, '\n');
+	return(0);
+}
+ 
+/*
+ * <offset> is byte offset for beginning of tilde string
+ */
+static void tilde_expand2(register int offset)
+{
+	char		shtilde[10], *av[3], *ptr=stakfreeze(1);
+	Sfio_t		*iop, *save=sfstdout;
+	Namval_t	*np;
+	static int	beenhere=0;
+	strcpy(shtilde,".sh.tilde");
+	np = nv_open(shtilde,sh.fun_tree, NV_VARNAME|NV_NOARRAY|NV_NOASSIGN|NV_NOFAIL);
+	if(np && !beenhere)
+	{
+		beenhere = 1;
+		sh_addbuiltin(shtilde,sh_btilde,0);
+	}
+	av[0] = ".sh.tilde";
+	av[1] = &ptr[offset];
+	av[2] = 0;
+	iop = sftmp(IOBSIZE+1);;
+	sfset(iop,SF_READ,0);
+	sfstdout = iop;
+	if(np)
+		sh_fun(np, (Namval_t*)0, av);
+	else
+		sh_btilde(2, av, &sh);
+	sfstdout = save;
+	stakset(ptr, offset);
+	sfseek(iop,(Sfoff_t)0,SEEK_SET);
+	sfset(iop,SF_READ,1);
+	if(ptr = sfreserve(iop, SF_UNBOUND, -1))
+	{
+		Sfoff_t n = sfvalue(iop);
+		while(ptr[n-1]=='\n')
+			n--;
+		if(n==1 && fcpeek(0)=='/' && ptr[n-1])
+			n--;
+		if(n)
+			stakwrite(ptr,n);
+	}
+	else
+		stakputs(av[1]);
+	sfclose(iop);
+}
+
+/*
+ * This routine is used to resolve ~ expansion.
+ * A ~ by itself is replaced with the users login directory.
+ * A ~- is replaced by the previous working directory in shell.
+ * A ~+ is replaced by the present working directory in shell.
+ * If ~name  is replaced with login directory of name.
+ * If string doesn't start with ~ or ~... not found then 0 returned.
+ */
+                                                            
+static char *sh_tilde(register const char *string)
+{
+	register char		*cp;
+	register int		c;
+	register struct passwd	*pw;
+	register Namval_t *np=0;
+	static Dt_t *logins_tree;
+	if(*string++!='~')
+		return(NIL(char*));
+	if((c = *string)==0)
+	{
+		if(!(cp=nv_getval(nv_scoped(HOME))))
+			cp = getlogin();
+		return(cp);
+	}
+	if((c=='-' || c=='+') && string[1]==0)
+	{
+		if(c=='+')
+			cp = nv_getval(nv_scoped(PWDNOD));
+		else
+			cp = nv_getval(nv_scoped(OLDPWDNOD));
+		return(cp);
+	}
+	if(logins_tree && (np=nv_search(string,logins_tree,0)))
+		return(nv_getval(np));
+	if(!(pw = getpwnam(string)))
+		return(NIL(char*));
+	if(!logins_tree)
+		logins_tree = dtopen(&_Nvdisc,Dtbag);
+	if(np=nv_search(string,logins_tree,NV_ADD))
+		nv_putval(np, pw->pw_dir,0);
+	return(pw->pw_dir);
+}
+
+/*
+ * return values for special macros
+ */
+static char *special(register int c)
+{
+	register Namval_t *np;
+	if(c!='$')
+		sh.argaddr = 0;
+	switch(c)
+	{
+	    case '@':
+	    case '*':
+		return(sh.st.dolc>0?sh.st.dolv[1]:NIL(char*));
+	    case '#':
+#if  SHOPT_FILESCAN
+		if(sh.cur_line)
+		{
+			getdolarg(&sh,MAX_ARGN,(int*)0);
+			return(ltos(sh.offsets[0]));
+		}
+#endif  /* SHOPT_FILESCAN */
+		return(ltos(sh.st.dolc));
+	    case '!':
+		if(sh.bckpid)
+			return(ltos(sh.bckpid));
+		break;
+	    case '$':
+		if(nv_isnull(SH_DOLLARNOD))
+			return(ltos(sh.pid));
+		return(nv_getval(SH_DOLLARNOD));
+	    case '-':
+		return(sh_argdolminus());
+	    case '?':
+		return(ltos(sh.savexit));
+	    case 0:
+		if(sh_isstate(SH_PROFILE) || !error_info.id || ((np=nv_search(error_info.id,sh.bltin_tree,0)) && nv_isattr(np,BLT_SPC)))
+			return(sh.shname);
+		else
+			return(error_info.id);
+	}
+	return(NIL(char*));
+}
+
+/*
+ * Handle macro expansion errors
+ */
+static void mac_error(Namval_t *np)
+{
+	if(np)
+		nv_close(np);
+	errormsg(SH_DICT,ERROR_exit(1),e_subst,fcfirst());
+}
+
+/*
+ * Given pattern/string, replace / with 0 and return pointer to string
+ * \ characters are stripped from string.
+ */ 
+static char *mac_getstring(char *pattern)
+{
+	register char *cp = pattern;
+	register int c;
+	while(c = *cp++)
+	{
+		if(c==ESCAPE)
+			cp++;
+		else if(c=='/')
+		{
+			cp[-1] = 0;
+			return(cp);
+		}
+	}
+	return(NIL(char*));
+}