From: Jim Huang <jserv@biilabs.io>
Date: Thu, 5 Aug 2021 06:28:12 +0000 (+0800)
Subject: cat_nonblock: Use canonical name scheme and fix unintended assignment
X-Git-Tag: latest~202
X-Git-Url: https://www.ivnss.com/gitweb/?a=commitdiff_plain;h=466e8a00fd604d1cd03b71f8e7d4fb04a0c6c6a5;p=lkmpg

cat_nonblock: Use canonical name scheme and fix unintended assignment
---

diff --git a/examples/other/cat_noblock.c b/examples/other/cat_noblock.c
deleted file mode 100644
index 42117cd..0000000
--- a/examples/other/cat_noblock.c
+++ /dev/null
@@ -1,64 +0,0 @@
-/*
- *  cat_noblock.c - open a file and display its contents, but exit rather than
- *  wait for input.
- */
-#include <errno.h>  /* for errno */
-#include <fcntl.h>  /* for open */
-#include <stdio.h>  /* standard I/O */
-#include <stdlib.h> /* for exit */
-#include <unistd.h> /* for read */
-
-#define MAX_BYTES 1024 * 4
-
-int main(int argc, char *argv[])
-{
-    int fd;                 /* The file descriptor for the file to read */
-    size_t bytes;           /* The number of bytes read */
-    char buffer[MAX_BYTES]; /* The buffer for the bytes */
-
-
-    /* Usage */
-    if (argc != 2) {
-        printf("Usage: %s <filename>\n", argv[0]);
-        puts("Reads the content of a file, but doesn't wait for input");
-        exit(-1);
-    }
-
-    /* Open the file for reading in non blocking mode */
-    fd = open(argv[1], O_RDONLY | O_NONBLOCK);
-
-    /* If open failed */
-    if (fd == -1) {
-        if (errno = EAGAIN)
-            puts("Open would block");
-        else
-            puts("Open failed");
-        exit(-1);
-    }
-
-    /* Read the file and output its contents */
-    do {
-        int i;
-
-        /* Read characters from the file */
-        bytes = read(fd, buffer, MAX_BYTES);
-
-        /* If there's an error, report it and die */
-        if (bytes == -1) {
-            if (errno = EAGAIN)
-                puts("Normally I'd block, but you told me not to");
-            else
-                puts("Another read error");
-            exit(-1);
-        }
-
-        /* Print the characters */
-        if (bytes > 0) {
-            for (i = 0; i < bytes; i++)
-                putchar(buffer[i]);
-        }
-
-        /* While there are no errors and the file isn't over */
-    } while (bytes > 0);
-    return 0;
-}
diff --git a/examples/other/cat_nonblock.c b/examples/other/cat_nonblock.c
new file mode 100644
index 0000000..50f3b67
--- /dev/null
+++ b/examples/other/cat_nonblock.c
@@ -0,0 +1,59 @@
+/*
+ *  cat_nonblock.c - open a file and display its contents, but exit rather than
+ *  wait for input.
+ */
+#include <errno.h>  /* for errno */
+#include <fcntl.h>  /* for open */
+#include <stdio.h>  /* standard I/O */
+#include <stdlib.h> /* for exit */
+#include <unistd.h> /* for read */
+
+#define MAX_BYTES 1024 * 4
+
+int main(int argc, char *argv[])
+{
+    int fd;                 /* The file descriptor for the file to read */
+    size_t bytes;           /* The number of bytes read */
+    char buffer[MAX_BYTES]; /* The buffer for the bytes */
+
+    /* Usage */
+    if (argc != 2) {
+        printf("Usage: %s <filename>\n", argv[0]);
+        puts("Reads the content of a file, but doesn't wait for input");
+        exit(-1);
+    }
+
+    /* Open the file for reading in non blocking mode */
+    fd = open(argv[1], O_RDONLY | O_NONBLOCK);
+
+    /* If open failed */
+    if (fd == -1) {
+        puts(errno == EAGAIN ? "Open would block" : "Open failed");
+        exit(-1);
+    }
+
+    /* Read the file and output its contents */
+    do {
+        /* Read characters from the file */
+        bytes = read(fd, buffer, MAX_BYTES);
+
+        /* If there's an error, report it and die */
+        if (bytes == -1) {
+            if (errno = EAGAIN)
+                puts("Normally I'd block, but you told me not to");
+            else
+                puts("Another read error");
+            exit(-1);
+        }
+
+        /* Print the characters */
+        if (bytes > 0) {
+            for (int i = 0; i < bytes; i++)
+                putchar(buffer[i]);
+        }
+
+        /* While there are no errors and the file isn't over */
+    } while (bytes > 0);
+
+    return 0;
+}
diff --git a/lkmpg.tex b/lkmpg.tex
index e5afe44..0bd97fa 100644
--- a/lkmpg.tex
+++ b/lkmpg.tex
@@ -1238,7 +1238,7 @@ There is one more point to remember. Some times processes don't want to sleep, t
 
 \begin{verbatim}
 $ sudo insmod sleep.ko
-$ cat_noblock /proc/sleep
+$ cat_nonblock /proc/sleep
 Last input:
 $ tail -f /proc/sleep &
 Last input:
@@ -1250,18 +1250,18 @@ Last input:
 Last input:
 tail: /proc/sleep: file truncated
 [1] 6540
-$ cat_noblock /proc/sleep
+$ cat_nonblock /proc/sleep
 Open would block
 $ kill %1
 [1]+  Terminated              tail -f /proc/sleep
-$ cat_noblock /proc/sleep
+$ cat_nonblock /proc/sleep
 Last input:
 $
 \end{verbatim}
 
 \samplec{examples/sleep.c}
 
-\samplec{examples/other/cat_noblock.c}
+\samplec{examples/other/cat_nonblock.c}
 
 \subsection{Completions}
 \label{sec:orgd9f9de4}