Category : C Source Code
Archive   : CINTERP.ZIP
Filename : SHELL.SCI

#
# Small c Interpreter command shell
#
# The library functions:
#
putchar(c){return sys(c,1,1)}
getchar(){return sys(0,2)}
puts(b){return sys(b,1,3)}
gets(b){return sys(b,80,0,4)}
fputc(c,u){return sys(c,u,1)}
fgetc(u){return sys(u,2)}
fputs(b,u){return sys(b,u,3)}
fgets(b,n,u){return sys(b,n,u,4)}
sprintf(a0,a1,a2,a3,a4,a5,a6,a7,a8,a9)
{return sys(a0,a1,a2,a3,a4,a5,a6,a7,a8,a9,5)}
printf(a0,a1,a2,a3,a4,a5,a6,a7,a8)
{char b[128];sys(b,a0,a1,a2,a3,a4,a5,a6,a7,a8,5);puts(b)}
sscanf(a0,a1,a2,a3,a4,a5,a6,a7,a8,a9)
{return sys(a0,a1,a2,a3,a4,a5,a6,a7,a8,a9,6)}
scanf(a0,a1,a2,a3,a4,a5,a6,a7,a8)
{char b[128];gets(b);sys(b,a0,a1,a2,a3,a4,a5,a6,a7,a8,6)}
atoi(b){int v;sys(b,"%d",&v,6);return v}
fopen(f,m){return sys(f,m,7)}
fread(s,l,u){return sys(s,l,u,8)}
fwrite(s,l,u){return sys(s,l,u,9)}
fclose(u){return sys(u,10)}
exit(){sys(11)}
stmt(l,p,s){return sys(l,p,s,12)}
totok(s,b){return sys(s,b,13)}
untok(b,s){return sys(b,s,14)}
edit(l,p){return sys(l,p,15)}
strcmp(s,t){return sys(s,t,16)}
strncmp(s,t,n){return sys(s,t,n,16)}
memleft(){return sys(17)}
malloc(n){return sys(n,18)}
free(p){sys(p,19)}
load(f,p){return sys(f,p,20)}
save(f,p){return sys(f,p,21)}
list(p,f,t){return sys(p,f,t,22)}
trace(n){sys(n,23)}

#
# Entry point to the shell. All globals defined before the "entry" keyword
# are in the "library" and are accessible by user programs.
#
entry

int size,top;
char line[80];
char program[16000];

main()
{
int from, to;

top=16000;
program[0]='Z'; # This is an "End of program" token - required
size=1;

# print sign-on message
printf("%s\nShell V1.2M, 13 Nov 1985\n",sys(0));

while(1)
{
puts("> ");
if(gets(line))
{
if (!strncmp(line,"edit",4))
size = sys(atoi(line+5),program,15); # envoke the editor
else if (!strncmp(line,"list",4))
{
if(line[4])
sscanf(line+4,"%d %d",&from,&to);
else
{
from=1;
to=32765;
}
sys(program,from,to,22); # list the program buffer
}
else if (!strncmp(line,"save",4))
sys(line+5,program,21); # save the program buffer
else if (!strncmp(line,"load",4))
size = sys(line+5,program,20); # load the program buffer
else if (!strncmp(line,"core",4))
printf("%d bytes free\n",top-size); # show amount of free space
else
{
#
# attempt to parse the line as a small c statement. Note that
# we will display (non-zero) results of a statement, so you
# could enter something like: 2+2 and a 4 would be printed.
#
printf("\n%d\n",sys(line,program,12));
}
}
}
}