longpath.c

unix高级编程源代码.<<unix高级编程>>

#include	<sys/types.h>
#include	<sys/stat.h>
#include	<fcntl.h>
#include	"ourhdr.h"

#define	DEPTH	100			/* directory depth */
#define	MYHOME	"/home/stevens"
#define	NAME	"alonglonglonglonglonglonglonglonglonglongname"

int
main(void)
{
	int		i, size;
	char	*path;

	if (chdir(MYHOME) < 0)
		err_sys("chdir error");

	for (i = 0; i < DEPTH; i++) {
		if (mkdir(NAME, DIR_MODE) < 0)
			err_sys("mkdir failed, i = %d", i);
		if (chdir(NAME) < 0)
			err_sys("chdir failed, i = %d", i);
	}
	if (creat("afile", FILE_MODE) < 0)
		err_sys("creat error");

	/*
	 * The deep directory is created, with a file at the leaf.
	 * Now let's try and obtain its pathname.
	 */

	path = path_alloc(&size);
	for ( ; ; ) {
		if (getcwd(path, size) != NULL)
			break;
		else {
			err_ret("getcwd failed, size = %d", size);
			size += 100;
			if ( (path = realloc(path, size)) == NULL)
				err_sys("realloc error");
		}
	}
	printf("length = %d\n%s\n", strlen(path), path);

	exit(0);
}