function_fread

1、functionfreadsize_tfread(voidptrsize_tsizesize_tcountFILEstream)ReadblockofdatafromstreamReadsanarrayofcountelementseachonewithasizeofsizebytesfromthestreamstesthemintheblockofmemyspecifiedbyptr.Thepositionindicatofthest

2、reamisadvancedbythetotalamountofbytesread.Thetotalamountofbytesreadifsuccessfulis(sizecount).ParametersptrPointertoablockofmemywithaminimumsizeof(sizecount)bytes.sizeSizeinbytesofeachelementtoberead.countNumberofelements

3、eachonewithasizeofsizebytes.streamPointertoaFILEobjectthatspecifiesaninputstream.ReturnValueThetotalnumberofelementssuccessfullyreadisreturnedasasize_tobjectwhichisanintegraldatatype.Ifthisnumberdiffersfromthecountparame

4、tereitheranerroccuredtheEndOfFilewasreached.YoucanuseeitherferrfeoftocheckwhetheranerrhappenedtheEndofFilewasreached.Example1234567891freadexample:readacompletefile#include#includeintmain()FILEpFilelonglSizebuffersize_tr

5、esult01112131415161718192021222324pFile=fopen(“myfile.bin““rb“)if(pFile==NULL)fputs(“Fileerr“stderr)exit(1)obtainfilesize:fseek(pFile0SEEK_END)lSize=ftell(pFile)rewind(pFile)allocatememytocontainthewholefile:buffer=()mal

6、loc(sizeof()lSize)if(buffer==NULL)fputs(“Memyerr“stderr)exit(2)copythefileintothebuffer:result=fread(buffer1lSizepFile)if(result!=lSize)fputs(“Readingerr“stderr)exit(3)thewholefileisnowloadedinthememybuffer.terminatefclo