grady@ucbvax.ARPA (Steven Grady) (04/16/85)
static char *sccsid = "@(#)echo.c 4.1 (Berkeley) 10/1/80";
#include <stdio.h>
main(argc, argv)
int argc;
char *argv[];
{
register int i, nflg, qflg, rflg;
srandom(getpid());
nflg = qflg = rflg = 0;
while (argc > 1 && argv[1][0] == '-' ){
i = 0;
while(argv[1][++i]){
switch (argv[1][i]){
case 'n': nflg++;
case 'q': qflg++;
case 'r': rflg++;
}
}
argc--;
argv++;
}
for(i=1; i<argc; i++) {
if ((! qflg) && ((! rflg) || (rflg && (random()&08)))) {
fputs(argv[i], stdout);
if (i < argc-1)
putchar(' ');
}
}
if(! nflg)
putchar('\n');
exit(0);
}grady@ucbvax.ARPA (Steven Grady) (04/16/85)
.TH ECHO 1 "15 April 1985" .SH NAME echo \- echo arguments .SH SYNOPSIS .B echo [ .B \-nqr ] [ arg ] ... .SH DESCRIPTION .I Echo writes its arguments separated by blanks and terminated by a newline on the standard output. If the flag .B \-n is used, no newline is added to the output. If the flag .B \-q is used, the .I echo runs quietly (arguments are not echoed). .B \-r is used to echo arguments randomly. .PP .I Echo is useful for producing diagnostics in shell programs and for writing constant data on pipes. To send diagnostics to the standard error file, do `echo ... 1>&2'. .I Echo with the .B \-q or .B \-r option is not useful.
ark@alice.UUCP (Andrew Koenig) (04/16/85)
> for(i=1; i<argc; i++) { > if ((! qflg) && ((! rflg) || (rflg && (random()&08)))) { > fputs(argv[i], stdout); > if (i < argc-1) > putchar(' '); > } random()&08? Is this some new kind of octal digit?
john@moncol.UUCP (John Ruschmeyer) (04/18/85)
As posted, the new 'echo' program has several bugs all stemming from missing 'break' statements in the loop which parses the arguments. The only visible bug, however, is that the '-n' option will also select the '-q' option and nothing will be printed. Also, the '-q' option should cause the '-n' option to be selected by default. This allows the program to be used to create an empty file, as in: echo -q foo >newfile The following diff shows the corrections which will take care of both problems: 16,18c16,18 < case 'n': nflg++; < case 'q': qflg++; < case 'r': rflg++; --- > case 'n': nflg++; break; > case 'q': qflg++; nflg++; break; > case 'r': rflg++; break; -- Name: John Ruschmeyer US Mail: Monmouth College, W. Long Branch, NJ 07764 Phone: (201) 222-6600 x366 UUCP: ...!vax135!petsd!moncol!john ...!princeton!moncol!john ...!pesnta!moncol!john Silly Quote: "Ah, but what is a dream but reality without a backbone?"
mroddy@enmasse.UUCP (Mark Roddy) (04/18/85)
[obsolete but impressive net bug feeder]
> random()&08? Is this some new kind of octal digit?
"The digits 8 and 9 have octal value 10 and 11 respectively."
{K&R ppg 180 sec 2.4.1}
Don't ask me I just work here.
*** ACE IS IN WITH OUR MESS ***
--
Mark Roddy
Net working,
Just reading the news.
(harvard!talcott!panda!enmasse!mroddy)piet@mcvax.UUCP (Piet Beertema) (04/19/85)
>if ((! qflg) && ((! rflg) || (rflg && (random()&08)))) { >random()&08? Is this some new kind of octal digit? Isn't "8" the only "octal" digit really worth it's name? -- Piet Beertema, CWI, Amsterdam ...{seismo,okstate,garfield,decvax,philabs}!mcvax!piet
dave@circadia.UUCP (David Messer) (04/25/85)
> > for(i=1; i<argc; i++) { > > if ((! qflg) && ((! rflg) || (rflg && (random()&08)))) { > > fputs(argv[i], stdout); > > if (i < argc-1) > > putchar(' '); > > } > > random()&08? Is this some new kind of octal digit? Yes! The new standard for octal is: 00-17(8) == 00-15(10). This allows for a greater range of octal constants and is seen as a new improvement to ADA. :-) -- Dave Messer ...ihnp4!stolaf!umn-cs!circadia!dave