【checkpass.c】
#include <stdio.h>
#include <string.h>
int checkpass(void){
int x;
char a[9];
x = 0;
fprintf(stderr,"a at %p and\nx at %p\n", (void *)a, (void *)&x);
printf("Enter a short word: ");
scanf("%s", a);
if (strcmp(a, "mypass") == 0)
x = 1;
return x;
}
[make.c]
#include <stdio.h>
int checkpass(void);
int main(void)
{
int x;
x = checkpass();
fprintf(stderr, "x = %d\n", x);
if (x)
fprintf(stderr, "Password is correct!\n");
else
fprintf(stderr, "Password is not correct!\n");
return 0;
}
[makefile]
LINT = lint ## lint check Code
LOPS = -x #-u
CC = cc #xlc ## 注意：大写'C' for c++
CC_FLAGS = #-q64 #-bnoquiet
INCLUDE= #-I. -I/usr/include -I/usr/vacpp/include
LIBPATH=#-L/usr/vacpp/lib -L/usr/lib -L/lib
PROGRAM = run
ALL : $(PROGRAM)
.SUFFIXES: .cpp .c .cc .cxx .o
.DEFAULT : all
SRCS = main.c checkpass.c
OBJS = $(SRCS:.c=.o)
$(PROGRAM) : $(OBJS)
$(CC) $(CC_FLAGS) $(INCLUDE) $(LIBPATH) $(OBJS) -o $(PROGRAM)
.c.o:
$(CC) $(INCLUDE) $(CC_FLAGS) -c $<
lintall: lint
lint:
$(LINT) $(LOPS) main.c checkpass.c
clean:
- rm -f ./*.o ./*.a ./$(PROGRAM)
[end]
操作系统的一个经典问题是"生产者-消费者"问题, 这涉及同步信号量和互斥信号量的应用, 在这里,我用线程的同步和互斥来实现.
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <pthread.h>
#include <semaphore.h>
#define N 2 // 消费者� ......
