[PATCH 0/2] fopencookie.3: Fix EXAMPLES section

[PATCH 0/2] fopencookie.3: Fix EXAMPLES section

[Alejandro Colomar]

*** BLURB HERE ***
Hi Michael,

I fixed a few bugs in the example program.

Testing the patch cover-letter now :)

Cheers,

Alex

Alejandro Colomar (2):
  fopencookie.3: printf()'s .* expects an int; cast accordingly
  fopencookie.3: Fix bugs in example

 man3/fopencookie.3 | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

-- 
2.28.0

[PATCH 1/2] fopencookie.3: printf()'s .* expects an int; cast accordingly

[Alejandro Colomar]

Signed-off-by: Alejandro Colomar <colomar.6.4.3@gmail.com>
---
 man3/fopencookie.3 | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/man3/fopencookie.3 b/man3/fopencookie.3
index 472a7f3d2..5394ce4a5 100644
--- a/man3/fopencookie.3
+++ b/man3/fopencookie.3
@@ -438,7 +438,7 @@ main(int argc, char *argv[])
             break;
         }
 
-        printf("/%.*s/\en", nread, buf);
+        printf("/%.*s/\en", (int) nread, buf);
     }
 
     exit(EXIT_SUCCESS);
-- 
2.28.0

[PATCH 2/2] fopencookie.3: Fix bugs in example

[Alejandro Colomar]

fread(3), unlike read(2) which returns a ssize_t, returns a size_t.
It doesn't distinguish between error and enf-of-file.
Instead, either ferror(3) or feof(3) need to be checked if
fread() returned 0.

Signed-off-by: Alejandro Colomar <colomar.6.4.3@gmail.com>
---
 man3/fopencookie.3 | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/man3/fopencookie.3 b/man3/fopencookie.3
index 5394ce4a5..055ec64d7 100644
--- a/man3/fopencookie.3
+++ b/man3/fopencookie.3
@@ -392,7 +392,7 @@ main(int argc, char *argv[])
     };
     FILE *stream;
     struct memfile_cookie mycookie;
-    ssize_t nread;
+    size_t nread;
     char buf[1000];
 
     /* Set up the cookie before calling fopencookie() */
@@ -429,11 +429,11 @@ main(int argc, char *argv[])
             exit(EXIT_FAILURE);
         }
         nread = fread(buf, 1, 2, stream);
-        if (nread == \-1) {
-            perror("fread");
-            exit(EXIT_FAILURE);
-        }
         if (nread == 0) {
+            if (ferror(stream) != 0) {
+                fprintf(stderr, "fread failed\en");
+                exit(EXIT_FAILURE);
+            }
             printf("Reached end of file\en");
             break;
         }
-- 
2.28.0

Re: [PATCH 1/2] fopencookie.3: printf()'s .* expects an int; cast accordingly

[Michael Kerrisk (man-pages)]

Hello ALex,

On 9/7/20 12:21 PM, Alejandro Colomar wrote:
> Signed-off-by: Alejandro Colomar <colomar.6.4.3@gmail.com>
> ---
>  man3/fopencookie.3 | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)

Thanks. Patch applied.

Cheers,

Michael

> diff --git a/man3/fopencookie.3 b/man3/fopencookie.3
> index 472a7f3d2..5394ce4a5 100644
> --- a/man3/fopencookie.3
> +++ b/man3/fopencookie.3
> @@ -438,7 +438,7 @@ main(int argc, char *argv[])
>              break;
>          }
>  
> -        printf("/%.*s/\en", nread, buf);
> +        printf("/%.*s/\en", (int) nread, buf);
>      }
>  
>      exit(EXIT_SUCCESS);
> 


-- 
Michael Kerrisk
Linux man-pages maintainer; http://www.kernel.org/doc/man-pages/
Linux/UNIX System Programming Training: http://man7.org/training/

Re: [PATCH 2/2] fopencookie.3: Fix bugs in example

[Michael Kerrisk (man-pages)]

Hello Alex,

On 9/7/20 12:21 PM, Alejandro Colomar wrote:
> fread(3), unlike read(2) which returns a ssize_t, returns a size_t.
> It doesn't distinguish between error and enf-of-file.
> Instead, either ferror(3) or feof(3) need to be checked if
> fread() returned 0.

Well, gosh, the person who wrote that example really 
should have read the documentation more closely :-}.

Thanks. Patch applied.

Cheers,

Michael

> Signed-off-by: Alejandro Colomar <colomar.6.4.3@gmail.com>
> ---
>  man3/fopencookie.3 | 10 +++++-----
>  1 file changed, 5 insertions(+), 5 deletions(-)
> 
> diff --git a/man3/fopencookie.3 b/man3/fopencookie.3
> index 5394ce4a5..055ec64d7 100644
> --- a/man3/fopencookie.3
> +++ b/man3/fopencookie.3
> @@ -392,7 +392,7 @@ main(int argc, char *argv[])
>      };
>      FILE *stream;
>      struct memfile_cookie mycookie;
> -    ssize_t nread;
> +    size_t nread;
>      char buf[1000];
>  
>      /* Set up the cookie before calling fopencookie() */
> @@ -429,11 +429,11 @@ main(int argc, char *argv[])
>              exit(EXIT_FAILURE);
>          }
>          nread = fread(buf, 1, 2, stream);
> -        if (nread == \-1) {
> -            perror("fread");
> -            exit(EXIT_FAILURE);
> -        }
>          if (nread == 0) {
> +            if (ferror(stream) != 0) {
> +                fprintf(stderr, "fread failed\en");
> +                exit(EXIT_FAILURE);
> +            }
>              printf("Reached end of file\en");
>              break;
>          }
> 


-- 
Michael Kerrisk
Linux man-pages maintainer; http://www.kernel.org/doc/man-pages/
Linux/UNIX System Programming Training: http://man7.org/training/