#!/bin/sh
# This is a shar archive.
# The rest of this file is a shell script which will extract:
#
# 3_7a.c 3_7a.cmp 3_7abtst.c 3_7b.c 3_7b.cmp 3_7c.c 3_7c.cmp 3_7ctst.c 3_7d.c 3_7d.cmp 3_7detst.c 3_7dtst.c 3_7e.c 3_7e.cmp 3_7f.c 3_7f.cmp 3_7fgtst.c 3_7g.c 3_7g.cmp makefile
#
# To extract the files from this shell archive file simply
# create a directory for this file, move the archive file
# to it and enter the command
#
#	sh filename
# 
# The files will be extracted automatically.
# Note: Do not use csh.
#
# Archive created: Mon Jul 30 22:59:26 EDT 1990
#
echo x - 3_7a.c
sed 's/^X//' > 3_7a.c << '!EOF!'
/* Copyright (c) 1990 by AT&T Bell Telephone Laboratories, Incorporated. */
/* The C++ Answer Book */
/* Tony Hansen */
/* All rights reserved. */
//  Count the characters within the string.
//  Version 1
int strlen(const char *s)
{
    int i = 0;
    while (*s++)
	i++;
    return i;
}

!EOF!
ls -l 3_7a.c
echo x - 3_7a.cmp
sed 's/^X//' > 3_7a.cmp << '!EOF!'
str='hello there', len=11
str='', len=0
str='This is a test', len=14
str='The quick brown fox jumped over the lazy brown dog', len=50
!EOF!
ls -l 3_7a.cmp
echo x - 3_7abtst.c
sed 's/^X//' > 3_7abtst.c << '!EOF!'
/* Copyright (c) 1990 by AT&T Bell Telephone Laboratories, Incorporated. */
/* The C++ Answer Book */
/* Tony Hansen */
/* All rights reserved. */
#include <stream.h>
#ifdef TSTA
# include "3_7a.c"
#endif
#ifdef TSTB
# include "3_7b.c"
#endif

char *x[] =
    {
    "hello there",
    "",
    "This is a test",
    "The quick brown fox jumped over the lazy brown dog",
    0
    };

main()
{
    for (char **xp = x; *xp; xp++)
	cout << "str='" << *xp << "', len=" << strlen(*xp) << "\n";
    return 0;
}
!EOF!
ls -l 3_7abtst.c
echo x - 3_7b.c
sed 's/^X//' > 3_7b.c << '!EOF!'
/* Copyright (c) 1990 by AT&T Bell Telephone Laboratories, Incorporated. */
/* The C++ Answer Book */
/* Tony Hansen */
/* All rights reserved. */
//  Count the characters within the string.
//  Version 2
int strlen(const char *s)
{
    const char *save = s;
    while (*s++)
	;
    return s - save - 1;
}
!EOF!
ls -l 3_7b.c
echo x - 3_7b.cmp
sed 's/^X//' > 3_7b.cmp << '!EOF!'
str='hello there', len=11
str='', len=0
str='This is a test', len=14
str='The quick brown fox jumped over the lazy brown dog', len=50
!EOF!
ls -l 3_7b.cmp
echo x - 3_7c.c
sed 's/^X//' > 3_7c.c << '!EOF!'
/* Copyright (c) 1990 by AT&T Bell Telephone Laboratories, Incorporated. */
/* The C++ Answer Book */
/* Tony Hansen */
/* All rights reserved. */
//  Count the characters within the string.
//  Version 3

//  Look in the first maxlen characters for a null
//  character.  Return its position (the length of
//  the string), or maxlen if it is not found.

int strnlen(const char *s, int maxlen)
{
    if (!s)
	return 0;
    int savemaxlen = maxlen;

    while (maxlen-- > 0)
	if (*s++ == '\0')
	    return savemaxlen - maxlen - 1;

    return savemaxlen;
}
!EOF!
ls -l 3_7c.c
echo x - 3_7c.cmp
sed 's/^X//' > 3_7c.cmp << '!EOF!'
str='hello there', max=0, len=0
str='', max=0, len=0
str='This is a test', max=0, len=0
str='The quick brown fox jumped over the lazy brown dog', max=0, len=0
str='hello there', max=4, len=4
str='', max=4, len=0
str='This is a test', max=4, len=4
str='The quick brown fox jumped over the lazy brown dog', max=4, len=4
str='hello there', max=8, len=8
str='', max=8, len=0
str='This is a test', max=8, len=8
str='The quick brown fox jumped over the lazy brown dog', max=8, len=8
str='hello there', max=12, len=11
str='', max=12, len=0
str='This is a test', max=12, len=12
str='The quick brown fox jumped over the lazy brown dog', max=12, len=12
str='hello there', max=16, len=11
str='', max=16, len=0
str='This is a test', max=16, len=14
str='The quick brown fox jumped over the lazy brown dog', max=16, len=16
!EOF!
ls -l 3_7c.cmp
echo x - 3_7ctst.c
sed 's/^X//' > 3_7ctst.c << '!EOF!'
/* Copyright (c) 1990 by AT&T Bell Telephone Laboratories, Incorporated. */
/* The C++ Answer Book */
/* Tony Hansen */
/* All rights reserved. */
#include <stream.h>
#include "3_7c.c"

char *x[] =
    {
    "hello there",
    "",
    "This is a test",
    "The quick brown fox jumped over the lazy brown dog",
    0
    };

main()
{
    for (int i = 0; i < 17; i += 4)
	for (char **xp = x; *xp; xp++)
	    cout << "str='" << *xp << "', max=" << i << ", len=" << strnlen(*xp, i) << "\n";
    return 0;
}
!EOF!
ls -l 3_7ctst.c
echo x - 3_7d.c
sed 's/^X//' > 3_7d.c << '!EOF!'
/* Copyright (c) 1990 by AT&T Bell Telephone Laboratories, Incorporated. */
/* The C++ Answer Book */
/* Tony Hansen */
/* All rights reserved. */
//  Copy the string s2 into s1.
//  Version 1
void strcpy(char *s1, const char *s2)
{
    while (*s1++ = *s2++)
	;
}
!EOF!
ls -l 3_7d.c
echo x - 3_7d.cmp
sed 's/^X//' > 3_7d.cmp << '!EOF!'
str=''
b=abcdefghijklmnopqrstuvwxyz
b=abc
str='hello there'
b=abcdefghijklmnopqrstuvwxyz
b=abchello there
str='This is a test'
b=abcdefghijklmnopqrstuvwxyz
b=abcThis is a test
str='The quick brown fox jumped over the lazy brown dog'
b=abcdefghijklmnopqrstuvwxyz
b=abcThe quick brown fox jumped over the lazy brown dog
!EOF!
ls -l 3_7d.cmp
echo x - 3_7detst.c
sed 's/^X//' > 3_7detst.c << '!EOF!'
/* Copyright (c) 1990 by AT&T Bell Telephone Laboratories, Incorporated. */
/* The C++ Answer Book */
/* Tony Hansen */
/* All rights reserved. */
#include <stream.h>

#ifdef TSTD
#include "3_7d.c"
#endif
#ifdef TSTE
#include "3_7e.c"
#endif

void* memcpy(void*, const void*, int);

char a[] = "abcdefghijklmnopqrstuvwxyz";
char b[3 * sizeof(a)];

char *x[] =
    {
    "",
    "hello there",
    "This is a test",
    "The quick brown fox jumped over the lazy brown dog",
    0
    };

main()
{
    for (char **xp = x; *xp; xp++)
        {
	memcpy(b, a, sizeof a);
	cout << "str='" << *xp << "'\n";
	cout << "b=" << b << "\n";
#ifdef TSTD
	strcpy(b+3, *xp);
#endif
#ifdef TSTE
	strncpy(b+3, sizeof(a)-3, *xp);
#endif
	cout << "b=" << b << "\n";
	}

    return 0;
}
!EOF!
ls -l 3_7detst.c
echo x - 3_7dtst.c
sed 's/^X//' > 3_7dtst.c << '!EOF!'
/* Copyright (c) 1990 by AT&T Bell Telephone Laboratories, Incorporated. */
/* The C++ Answer Book */
/* Tony Hansen */
/* All rights reserved. */
#include <stream.h>

void* memcpy(void*, const void*, int);

char a[] = "abcdefghijklmnopqrstuvwxyz";
char b[sizeof a];

main()
{
    memcpy(b, a, sizeof a);
    strcpy(a+3, "");
    cout << "a=" << a << "\n";
    memcpy(b, a, sizeof a);
    strcpy(a+3, "QRSTUVWXYZ");
    cout << "a=" << a << "\n";
    return 0;
}
!EOF!
ls -l 3_7dtst.c
echo x - 3_7e.c
sed 's/^X//' > 3_7e.c << '!EOF!'
/* Copyright (c) 1990 by AT&T Bell Telephone Laboratories, Incorporated. */
/* The C++ Answer Book */
/* Tony Hansen */
/* All rights reserved. */
//  Copy the string s2 into s1.
//  Version 2
void strncpy(char *s1, int maxlen, const char *s2)
{
    if (s1 && s2)
	{
	while (--maxlen)
	    if (!(*s1++ = *s2++))
		return;

	if (maxlen > 0)
	    *s1 = '\0';
	}
}
!EOF!
ls -l 3_7e.c
echo x - 3_7e.cmp
sed 's/^X//' > 3_7e.cmp << '!EOF!'
str=''
b=abcdefghijklmnopqrstuvwxyz
b=abc
str='hello there'
b=abcdefghijklmnopqrstuvwxyz
b=abchello there
str='This is a test'
b=abcdefghijklmnopqrstuvwxyz
b=abcThis is a test
str='The quick brown fox jumped over the lazy brown dog'
b=abcdefghijklmnopqrstuvwxyz
b=abcThe quick brown fox jum
!EOF!
ls -l 3_7e.cmp
echo x - 3_7f.c
sed 's/^X//' > 3_7f.c << '!EOF!'
/* Copyright (c) 1990 by AT&T Bell Telephone Laboratories, Incorporated. */
/* The C++ Answer Book */
/* Tony Hansen */
/* All rights reserved. */
//    Compare two strings. Return <0, >0 or 0
//    when the first string is lexically
//    less than, greater than, or equal to
//    the second, respectively.

int strcmp(const char *s1, const char *s2)
{
    if (s1 && s2)
	{
	while (*s1)
	    if (*s1++ != *s2++)
#ifdef TSTG		/* DELETE */
# include "3_7g.c"	/* DELETE */
#else			/* DELETE */
		return s1[-1] - s2[-1];
#endif			/* DELETE */
	return *s1 - *s2;
	}

    else
	error("NULL pointer encountered");
}
!EOF!
ls -l 3_7f.c
echo x - 3_7f.cmp
sed 's/^X//' > 3_7f.cmp << '!EOF!'
a='abcd', b='abcd'
cmp=0
a='abc', b='abcd'
cmp=-100
a='abcd', b='abc'
cmp=100
a='abdc', b='abcd'
cmp=1
a='abdc', b='abcda'
cmp=1
a='abdc', b='abc'
cmp=1
!EOF!
ls -l 3_7f.cmp
echo x - 3_7fgtst.c
sed 's/^X//' > 3_7fgtst.c << '!EOF!'
/* Copyright (c) 1990 by AT&T Bell Telephone Laboratories, Incorporated. */
/* The C++ Answer Book */
/* Tony Hansen */
/* All rights reserved. */
#include <stream.h>
#include <error.h>

#include "3_7f.c"

struct sp
    { char *a, *b; } x[] = {
	{ "abcd", "abcd" },
	{ "abc", "abcd" },
	{ "abcd", "abc" },
	{ "abdc", "abcd" },
	{ "abdc", "abcda" },
	{ "abdc", "abc" },
	{ 0, 0 }
    };

main()
{
    for (sp *xp = x; xp->a; xp++)
	{
	cout << "a='" << xp->a << "', b='" << xp->b << "'\n";
	cout << "cmp=" << strcmp(xp->a, xp->b) << "\n";
	}

    return 0;
}
!EOF!
ls -l 3_7fgtst.c
echo x - 3_7g.c
sed 's/^X//' > 3_7g.c << '!EOF!'
/* Copyright (c) 1990 by AT&T Bell Telephone Laboratories, Incorporated. */
/* The C++ Answer Book */
/* Tony Hansen */
/* All rights reserved. */
return *--s1 - *--s2;
!EOF!
ls -l 3_7g.c
echo x - 3_7g.cmp
sed 's/^X//' > 3_7g.cmp << '!EOF!'
a='abcd', b='abcd'
cmp=0
a='abc', b='abcd'
cmp=-100
a='abcd', b='abc'
cmp=100
a='abdc', b='abcd'
cmp=1
a='abdc', b='abcda'
cmp=1
a='abdc', b='abc'
cmp=1
!EOF!
ls -l 3_7g.cmp
echo x - makefile
sed 's/^X//' > makefile << '!EOF!'
CC= CC -I. -I../../CC
ERROR=  ../../error.o
all: 3_7atst 3_7btst 3_7ctst 3_7dtst 3_7etst 3_7ftst 3_7gtst

3_7atst: 3_7abtst.c 3_7a.c	# strlen
	$(CC) -DTSTA 3_7abtst.c -o 3_7atst $(ERROR)

3_7btst: 3_7abtst.c 3_7b.c	# strlen
	$(CC) -DTSTB 3_7abtst.c -o 3_7btst $(ERROR)

3_7ctst: 3_7ctst.c 3_7c.c	# strnlen
	$(CC) 3_7ctst.c -o 3_7ctst $(ERROR)

3_7dtst: 3_7detst.c 3_7d.c	# strcpy
	$(CC) -DTSTD 3_7detst.c -o 3_7dtst $(ERROR)

3_7etst: 3_7detst.c 3_7e.c	# strncpy
	$(CC) -DTSTE 3_7detst.c -o 3_7etst $(ERROR)

3_7ftst: 3_7fgtst.c 3_7f.c	# strcmp
	$(CC) -DTSTF 3_7fgtst.c -o 3_7ftst $(ERROR)

3_7gtst: 3_7fgtst.c 3_7f.c 3_7g.c	# strcmp ret2
	$(CC) -DTSTG 3_7fgtst.c -o 3_7gtst $(ERROR)

test: all 3_7a.cmp 3_7b.cmp 3_7c.cmp 3_7d.cmp 3_7e.cmp 3_7f.cmp 3_7g.cmp 
	3_7atst > 3_7a.out
	cmp 3_7a.out 3_7a.cmp
	3_7btst > 3_7b.out
	cmp 3_7b.out 3_7b.cmp
	3_7ctst > 3_7c.out
	cmp 3_7c.out 3_7c.cmp
	3_7dtst > 3_7d.out
	cmp 3_7d.out 3_7d.cmp
	3_7etst > 3_7e.out
	cmp 3_7e.out 3_7e.cmp
	3_7ftst > 3_7f.out
	cmp 3_7f.out 3_7f.cmp
	3_7gtst > 3_7g.out
	cmp 3_7g.out 3_7g.cmp
	echo tests done
!EOF!
ls -l makefile
# The following exit is to ensure that extra garbage 
# after the end of the shar file will be ignored.
exit 0