Link Error
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here, contact cs106-pchelp@cs.stanford.edu. Question: I am getting the link error "unresolved external symbol" for functions that
Linking Error Undefined Reference To Function
were provided with the assignment starter project. I checked and the linker error c++ function name is the same as listed in the .h file. Example: I am working on the linker error undefined reference to battleship assignment,and I have a problem with the battlegraphics.h library. I get the following message from my compiler (MS Visual C++ 6.0): Linking... BATTLESH.OBJ : error LNK2001: unresolved
C++ Linker Error Unresolved External Symbol
external symbol _DrawStartingBoard Debug/battleship.exe : fatal error LNK1120: 1 unresolved externals Error executing link.exe. battleship.exe - 2 error(s), 3 warning(s) What's going on? Answer: There's a difference between interface and implementation. A .h file (such as battlegraphics.h) defines the interface for a group of related functions. That is, it tells you (and the compiler) what functions
Link Error C++
exist, how to call them, what their arguments and return types are, etc. But you'll notice that there is no code there that would tell the compiler what steps to carry out if you call DrawStartingBoard() -- only that such a function exists and takes such and such arguments. That is where the implementation comes in. The implementation of a function is the code that defines its execution. This can be in a .c file; for example, in the course of a normal assignment or program, you implement many functions. In some cases, we will provide you with .cpp files containing the implementation for functions that may use as-is, look at, or modify. The implementation can also be contained in a .lib file (library) containing already-compiled code; we may provide you with .lib files instead of .cpp files in cases where the implementation source is unimportant or needs to remain a secret. Either way, when you #include a .h file, you've only told the compile
Practice Problems Quizzes Resources Source Code Source Code Snippets C and C++ Tips Finding a Job References Function Reference Syntax Reference Programming FAQ Getting Help Message error lnk2019: unresolved external symbol Board Email About Us Dealing with Compiler Errors - Surviving the Compilation
Lnk2001
Process By Alex Allain It's your first C (or C++) program--it's not that long, and you're about to ld returned 1 exit status compile it. You hit compile (or enter the build command) and wait. Your compiler spits out fifty lines of text. You pick out words like "warning and "error". Does that http://web.stanford.edu/class/cs/compilers/106libs/pc/pclib-faq/link-error.html mean it worked? you wonder. You look for the resulting executable. Nothing. Damn, you think, I guess I have to figure out what this all means... The Types of Compilation Errors First, let's distinguish between the types of errors: most compilers will give three types of compile-time alerts: compiler warnings, compiler errors, and linker errors. Although you don't want to http://www.cprogramming.com/tutorial/compiler_linker_errors.html ignore them, compiler warnings aren't something severe enough to actually keep your program from compiling. Usually, compiler warnings are an indication that something might go wrong at runtime. How can the compiler know this at all? You might be making a typical mistake that the compiler knows about. A common example is using the assignment operator ('=') instead of the equality operator ('==') inside an if statement. Your compiler may also warn you about using variables that haven't been initialized and other similar mistakes. Generally, you can set the warning level of your compiler--I like to keep it at its highest level so that my compiler warnings don't turn in to bugs in the running program ('runtime bugs'). Nevertheless, compiler warnings aren't going to stop you from getting your program working (unless you tell your compiler to treat warnings as errors), so they're probably a bit less frustrating than errors. Errors are conditions that prevent the compiler from completing the compilation of your files. Compiler errors are restricted to single source code files and are the result of
here for a quick overview of the site Help Center Detailed answers to any questions you might have Meta Discuss the workings and policies of this site About Us Learn more about Stack Overflow the company Business Learn more about hiring developers http://stackoverflow.com/questions/3359283/wsastartup-link-error or posting ads with us Stack Overflow Questions Jobs Documentation Tags Users Badges Ask Question https://community.sophos.com/products/unified-threat-management/f/general-discussion/22777/wan-link-crashing-state-up-link-error x Dismiss Join the Stack Overflow Community Stack Overflow is a community of 6.2 million programmers, just like you, helping each other. Join them; it only takes a minute: Sign up WSAStartup link error up vote 1 down vote favorite I am using EVC++ and I want to compile the program which uses the sockets. I've included #include
Home Sophos UTM 9 Sophos XG Firewall Web Appliance General Malware [Beta] Malware Course Sophos Intercept X Sophos Wireless Knowledge Base Blog Sophos UTM 9 General Discussion WAN link "crashing"… UTM 9 Release Notes UTM Wiki Knowledge Base Sub-Groups Cancel This group requires membership for participation - click to join Thread Info State Not Answered Date brimur Date 12 Aug 2015 4:17 PM Replies 7 replies Subscribers 1 subscriber Views 845 views English Suggested Have a cool product idea or improvement? We'd love to hear about it! Click here to go to the product suggestion community WAN link "crashing"... State: UP Link: Error SophosUTMHomerunningonlicensedESXi6.0 Higuys, IamexperiencingastrangeissuewheretheWANlinkjuststopsworking.WhenIlogintotheadminconsoleIseeState:UPLink:Error Ihave3virtualEthernetconnections:LAN,WAN,WANBackup LANmapstoaphysicalportgoingtomyLANswitch WANandWANBackupmaptoasinglephysicalportgoingtomycablemodem. IaddedWANBackupandUplinkBalancingtotackletheissueanditworkedforawhile.WANwouldcrashandfailovertoWANBackup(samephysicalport)andtheconnectionwouldcontinuetowork. LatelyhoweverWANandWANBackupwillhavethesameissueState:UPLink:Error Thecablemodemhas4portsandasolidconnection.Ihaveawirelessrouterconnecteddirectlytothecablemodemforguestwifiaccessanditdoesnotloseconnection.IconnecttothistoverifythemodemisstillworkingwhentheinternetstopsworkingfortheLAN. ThereareneverissueswiththeLANconnectionandIneverhaveanyproblemsloggingintoUTMwhentheconnectionisdownoranyothertime. Ihavetriedswappingoutallcablesinvolvedwithnodifference Anyideashowtotroubleshootthisfurtherorwhatlogstolookat? Thanks Cancel ignitor 0 12 Aug 2015 8:54 PM Wehavehadthishappentodevicesconnectedtoacablemodemtoo.However,inourcasethesewerehardwareconnectionstoacablemodem.LinkerrorswerealwaysrelatedtoissuesontheISPend.I'msuresomeonemaybeabletoshedabitmorelightintohowtheUTMdetectsLinkerrorsandwhattheygenerallymean.Curious-Isthemodemyoumentionedinbridgedmode? William Warren 0 13 Aug 2015 7:29 AM SophosUTMHomerunningonlicensedESXi6.0Higuys,IamexperiencingastrangeissuewheretheWANlinkjuststopsworking.WhenIlogintotheadminconsoleIseeState:UPLink:ErrorIhave3virtualEthernetconnections:LAN,WAN,WANBackupLANmapstoaphysicalportgoingtomyLANswitchWANandWANBackupmaptoasinglephysicalportgoingtomycablemodem.IaddedWANBackupandUplinkBalancingtotackletheissueanditworkedforawhile.WANwouldcrashandfailovertoWANBackup(samephysicalport)andtheconnectionwouldcontinuetowork.LatelyhoweverWANandWANBackupwillhaveth