c++ 질문 드립니다.

$ diff -u memdjpeg.c memdjpeg.cpp
--- memdjpeg.c  2021-02-22 13:11:41.830191114 +0900
+++ memdjpeg.cpp        2021-02-24 08:41:44.959063413 +0900
@@ -20,8 +20,9 @@
 #include <syslog.h>
 #include <sys/stat.h>
 
-#include <jpeglib.h>
+#include <iostream>
 
+#include <jpeglib.h>
 
 int main (int argc, char *argv[]) {
        int rc, i, j;
@@ -98,6 +99,7 @@
        // so it's likely you'll want to replace it or supplement it with
        // your own.
        cinfo.err = jpeg_std_error(&jerr);
+       jerr.error_exit = [](j_common_ptr cinfo){throw cinfo->err;};
        jpeg_create_decompress(&cinfo);
 
 
@@ -118,7 +120,18 @@
        // Have the decompressor scan the jpeg header. This won't populate
        // the cinfo struct output fields, but will indicate if the
        // jpeg is valid.
-       rc = jpeg_read_header(&cinfo, TRUE);
+       try
+       {
+               rc = jpeg_read_header(&cinfo, TRUE);
+       }
+       catch (struct jpeg_error_mgr *err)
+       {
+               char pszErr[1024];
+               (cinfo.err->format_message)((j_common_ptr)&cinfo, pszErr);
+               std::cerr << "Exception Caught : ";
+               std::cerr << pszErr << std::endl;
+               return 100;
+       }
 
        if (rc != 1) {
                syslog(LOG_ERR, "File does not seem to be a normal JPEG");

$ g++ memdjpeg.cpp -ljpeg -o memdjpeg
$ ./memdjpeg __art\[1\].jpg
./memdjpeg[3107904]: Input: Read 565022/565022 bytes
./memdjpeg[3107904]: Proc: Create Decompress struct
./memdjpeg[3107904]: Proc: Set memory buffer as source
./memdjpeg[3107904]: Proc: Read the JPEG header
Exception Caught : Not a JPEG file: starts with 0x89 0x50
$ echo $?
100