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#include <errno.h>
#include <string.h>
#include <fcntl.h>
#include <stdlib.h>
#include <unistd.h>
#include <stdio.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <dirent.h>
/* The C Programming Language: 2nd Edition
*
* Exercise 8-5: Modify the fsize program to print the other information
* contained in the inode entry.
*
* Notes: The supplied header file examples don't really work well on a
* GNU/Linux system in 2022. :) This makes 8-5 the only exercise in the book
* that's broken enough to nearly require the standard library to complete.
* Despite lacking the homegrown headers, this exercise is still a good example
* of callbacks.
*
* Not all of the information within the stat struct is displayed by this
* program; this is mostly due to the information not being terribly useful
* on all systems. Modification time and permission information is relevant
* to all platforms.
*/
void fsize(char *);
void dirwalk(char *, void (*fcn)(char *));
int main(int argc, char **argv) {
if (argc == 1) {
fsize(".");
} else {
while (--argc > 0) {
fsize(*++argv);
}
}
return 0;
}
void fsize(char *name) {
struct stat stbuf;
if (stat(name, &stbuf) == -1) {
fprintf(stderr, "fsize: can't access %s\n", name);
return;
}
if ((stbuf.st_mode & S_IFMT) == S_IFDIR) {
dirwalk(name, fsize);
}
/*
* Size, Mode, UID, GID, ModifiedTime, FileName
*/
printf("%8ld %6o %d %d %ld %s\n", stbuf.st_size, stbuf.st_mode, stbuf.st_uid, stbuf.st_gid, stbuf.st_mtime, name);
}
void dirwalk(char *dir, void (*fcn)(char *)) {
char name[PATH_MAX];
struct dirent *dp;
DIR *dfd;
if ((dfd = opendir(dir)) == NULL) {
fprintf(stderr, "dirwalk: can't open %s\n", dir);
return;
}
while ((dp = readdir(dfd)) != NULL) {
if (strcmp(dp->d_name, ".") == 0 || strcmp(dp->d_name, "..") == 0) {
continue;
}
if (strlen(dir)+strlen(dp->d_name)+2 > sizeof (name)) {
fprintf(stderr, "dirwalk: name %s/%s too long\n", dir, dp->d_name);
} else {
sprintf(name, "%s/%s", dir, dp->d_name);
(*fcn)(name);
}
}
closedir(dfd);
}
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