docs/examples: adjust prototypes for CURLOPT_READFUNCTION

The type of the buffer in curl_read_callback is 'char *', not 'void *'.

Signed-off-by: Olaf Hering <olaf@aepfle.de>
Closes #6392

docs/examples/anyauthput.c

@@ -78,7 +78,7 @@ static curlioerr my_ioctl(CURL *handle, curliocmd cmd, void *userp)
 }
 
 /* read callback function, fread() look alike */
-static size_t read_callback(void *ptr, size_t size, size_t nmemb, void *stream)
+static size_t read_callback(char *ptr, size_t size, size_t nmemb, void *stream)
 {
   ssize_t retcode;
   curl_off_t nread;

docs/examples/curlgtk.c

@@ -24,7 +24,7 @@ size_t my_write_func(void *ptr, size_t size, size_t nmemb, FILE *stream)
   return fwrite(ptr, size, nmemb, stream);
 }
 
-size_t my_read_func(void *ptr, size_t size, size_t nmemb, FILE *stream)
+size_t my_read_func(char *ptr, size_t size, size_t nmemb, FILE *stream)
 {
   return fread(ptr, size, nmemb, stream);
 }

docs/examples/ftpupload.c

@@ -48,7 +48,7 @@
    DLL, you MUST also provide a read callback with CURLOPT_READFUNCTION.
    Failing to do so will give you a crash since a DLL may not use the
    variable's memory when passed in to it from an app like this. */
-static size_t read_callback(void *ptr, size_t size, size_t nmemb, void *stream)
+static size_t read_callback(char *ptr, size_t size, size_t nmemb, void *stream)
 {
   curl_off_t nread;
   /* in real-world cases, this would probably get this data differently

docs/examples/ftpuploadfrommem.c

@@ -43,7 +43,7 @@ struct WriteThis {
   size_t sizeleft;
 };
 
-static size_t read_callback(void *ptr, size_t size, size_t nmemb, void *userp)
+static size_t read_callback(char *ptr, size_t size, size_t nmemb, void *userp)
 {
   struct WriteThis *upload = (struct WriteThis *)userp;
   size_t max = size*nmemb;

docs/examples/ftpuploadresume.c

@@ -51,7 +51,7 @@ static size_t discardfunc(void *ptr, size_t size, size_t nmemb, void *stream)
 }
 
 /* read data to upload */
-static size_t readfunc(void *ptr, size_t size, size_t nmemb, void *stream)
+static size_t readfunc(char *ptr, size_t size, size_t nmemb, void *stream)
 {
   FILE *f = stream;
   size_t n;

docs/examples/http2-upload.c

@@ -159,7 +159,7 @@ int my_trace(CURL *handle, curl_infotype type,
   return 0;
 }
 
-static size_t read_callback(void *ptr, size_t size, size_t nmemb, void *userp)
+static size_t read_callback(char *ptr, size_t size, size_t nmemb, void *userp)
 {
   struct input *i = userp;
   size_t retcode = fread(ptr, size, nmemb, i->in);

docs/examples/httpput.c

@@ -38,7 +38,7 @@
  * http://www.apacheweek.com/features/put
  */
 
-static size_t read_callback(void *ptr, size_t size, size_t nmemb, void *stream)
+static size_t read_callback(char *ptr, size_t size, size_t nmemb, void *stream)
 {
   size_t retcode;
   curl_off_t nread;

docs/examples/imap-append.c

@@ -59,7 +59,7 @@ struct upload_status {
   int lines_read;
 };
 
-static size_t payload_source(void *ptr, size_t size, size_t nmemb, void *userp)
+static size_t payload_source(char *ptr, size_t size, size_t nmemb, void *userp)
 {
   struct upload_status *upload_ctx = (struct upload_status *)userp;
   const char *data;

docs/examples/post-callback.c

@@ -41,7 +41,7 @@ struct WriteThis {
   size_t sizeleft;
 };
 
-static size_t read_callback(void *dest, size_t size, size_t nmemb, void *userp)
+static size_t read_callback(char *dest, size_t size, size_t nmemb, void *userp)
 {
   struct WriteThis *wt = (struct WriteThis *)userp;
   size_t buffer_size = size*nmemb;

docs/examples/sftpuploadresume.c

@@ -29,7 +29,7 @@
 #include <curl/curl.h>
 
 /* read data to upload */
-static size_t readfunc(void *ptr, size_t size, size_t nmemb, void *stream)
+static size_t readfunc(char *ptr, size_t size, size_t nmemb, void *stream)
 {
   FILE *f = (FILE *)stream;
   size_t n;

docs/examples/smtp-authzid.c

@@ -67,7 +67,7 @@ struct upload_status {
   int lines_read;
 };
 
-static size_t payload_source(void *ptr, size_t size, size_t nmemb, void *userp)
+static size_t payload_source(char *ptr, size_t size, size_t nmemb, void *userp)
 {
   struct upload_status *upload_ctx = (struct upload_status *)userp;
   const char *data;

docs/examples/smtp-mail.c

@@ -64,7 +64,7 @@ struct upload_status {
   int lines_read;
 };
 
-static size_t payload_source(void *ptr, size_t size, size_t nmemb, void *userp)
+static size_t payload_source(char *ptr, size_t size, size_t nmemb, void *userp)
 {
   struct upload_status *upload_ctx = (struct upload_status *)userp;
   const char *data;

docs/examples/smtp-multi.c

@@ -61,7 +61,7 @@ struct upload_status {
   int lines_read;
 };
 
-static size_t payload_source(void *ptr, size_t size, size_t nmemb, void *userp)
+static size_t payload_source(char *ptr, size_t size, size_t nmemb, void *userp)
 {
   struct upload_status *upload_ctx = (struct upload_status *)userp;
   const char *data;

docs/examples/smtp-ssl.c

@@ -61,7 +61,7 @@ struct upload_status {
   int lines_read;
 };
 
-static size_t payload_source(void *ptr, size_t size, size_t nmemb, void *userp)
+static size_t payload_source(char *ptr, size_t size, size_t nmemb, void *userp)
 {
   struct upload_status *upload_ctx = (struct upload_status *)userp;
   const char *data;

docs/examples/smtp-tls.c

@@ -61,7 +61,7 @@ struct upload_status {
   int lines_read;
 };
 
-static size_t payload_source(void *ptr, size_t size, size_t nmemb, void *userp)
+static size_t payload_source(char *ptr, size_t size, size_t nmemb, void *userp)
 {
   struct upload_status *upload_ctx = (struct upload_status *)userp;
   const char *data;