I've been asked to write test programs on 4 functions in the card game dominion. I've written one (extremely simple) just to make sure I can get it to pass as I'm pretty new to testing. However, I continually get a syntax error at runtime that I cannot figure out.
#include <stdlib.h>
#include <stdio.h>
#include <assert.h>
#include "dominion.h"
#include "dominion_helpers.h"
#include "rngs.h"
int main() {
int r = 0, j = 0;
int adventurer = 8;
int greathall = 17;
r = getCost(adventurer);
assert(r == 6);
j = getCost(greathall);
assert(j == 3);
return 0;
}
When I compile it, I do get some warnings:
Undefined symbols for architecture x86_64:
"_getCost", referenced from:
_main in unittest1-7d7bf2.o
ld: symbol(s) not found for architecture x86_64
clang: error: linker command failed with exit code 1 (use -v to see invocation)
Which I'm not sure about either, but the base code that we are given from our instructor, as well as all of the other code from my classmates, has these warnings as well.
However, when running I get the following error:
./unittest1.c: line 8: syntax error near unexpected token `('
./unittest1.c: line 8: `int main() {'
I've tried rewriting it in a blank file thinking there was some invisible characters or something but I still get this error. Does anyone see something wrong in my code? Any help is appreciated.
**getCost is called in dominion_helpers
I am working on this tutorial on building your own LISP (http://www.buildyourownlisp.com/chapter4_interactive_prompt) and for some reason when I try to compile I get this:
REPL.c:4:10: fatal error: 'editline/readline.h' file not found
#include <editline/history.h>
^
1 error generated.
I have installed the macOS developer tools, and brew is showing readline is installed and it doesn't know what to do when I try brew install editline.
This is my code:
1 #include <stdio.h>
2 #include <stdlib.h>
3 #include <editline/readline.h>
4 #include <editline/history.h>
5
6 int main(int argc, char** argv) {
7
8 /* version/exit info */
9 puts("Edward Version 0.0.1");
10 puts("Press Ctrl+c to Exit\n");
11
12 /* endless loop for main REPL */
13 while (1) {
14 /* output prompt and read line */
15 char* input = readline("lispy> ");
16
17 /* put input in history */
18 add_history(input);
19
20 /* Echo input back */
21 printf("No you're a %s\n", input);
22
23 /* free input */
24 free(input);
25 }
26 return 0;
27 }
It is obviously very basic, but I really want to get this project rolling so I'm hoping I can figure this out. This is what I'm using to compile:
cc -std=c99 -Wall REPL.c -ledit -o REPL
Include only
#include <editline/readline.h>
which should exist if the command line tools are installed. This file contains the
"readline wrapper" for libedit, including the history functions as well.
An include file <editline/history.h> does not exist on OS X.
I tested your code with that modification, and it compiled and ran without problems.
Using OSX Yosemite. I removed #include<editline/history.h>
and then used cc -std=c99 -Wall test.c -ledit -o test
Works fine now
I'm on El Capitan,
Remove #include <editline/history.h>,
and use cc -std=c99 -Wall test.c -ledit -o test works for me.
Add the flag -ledit before the output flad, it's a linking process, allows the compiler to directly embed calls to editline in your program. Or, you'll get the below error message,
Undefined symbols for architecture x86_64:
"_add_history", referenced from:
_main in prompt-086f90.o
"_readline", referenced from:
_main in prompt-086f90.o
ld: symbol(s) not found for architecture x86_64
I'm on Ubuntu 14.04.
try this:
sudo apt-get install libeditline-dev
and include like this:
#include <editline.h>
finally compile like this:
add -leditline in the flag
I hope this can help.
I'm on OSX Mavericks and removing the line worked for me:
#include <editline/history.h>
The solution for those following along on FreeBSD (might work on other Unices as well):
#include <stdio.h>
#include <stdlib.h>
#include <readline/readline.h>
#include <readline/history.h>
...
And run:
$ cc test.c -Wall -std=c99 -lreadline -o test
Without "-lreadline" in the compile step it is not linked in and you will get errors about undefined reference to "readline" function.
I started in on Build your own list and ran into the same problem.
None of the above answers worked for me. After a little research I found out that macOs doesn't have the gnu readline library that provides the readline functions, Different versions of MacOs provide emulation of readline using a library called editline. to begin...
man editline
#include <histedit.h>
Ok, editline gives you some structs for line input and history,
and functions to operate on them. First you have to instantiate these structs. The documentation for editline is not very helpful because it doesn't contain any examples. Apple makes the header file available so that helps a little. http://www.opensource.apple.com/source/libedit/libedit-13/src/histedit.h
I am new to this and it was still pretty confusing to me. there is some version of the source code to libedit available as a debian package. Fortunately someone wiser than I has already dug into it and implemented a command line using lbedit. His code is here: https://www.cs.utah.edu/~bigler/code/libedit.html.
I took Mr Bigler's code, and the code from Build your own list, and put them together to get this.
/* repl-macos.c
* Repl code example from builyourownlisp.com
* Modified by NB aug 2017
* Code example for editline from
* www.cs.utah.edu/~bigler/code/libedit.html
*/
#include <stdio.h>
#include <string.h>
#include <histedit.h>
char* prompt(EditLine *e){
return "lispy> ";
}
int main(int argc, char** argv){
EditLine *el; // Line editor state
History *herstory; // the rest is history
// Temp Variables
int count;
const char *usrin;
int keepreading = 1;
HistEvent ev;
// Initialize the editline state
el = el_init(argv[0], stdin, stdout, stderr);
el_set(el, EL_PROMPT, &prompt);
el_set(el, EL_EDITOR, "emacs");
// Initialize history
herstory = history_init();
if(!herstory){
fprintf(stderr, "Couldn't initialize history\n");
return 1;
}
//set history size
history(herstory, &ev, H_SETSIZE, 800);
// Set up the call back functions for history functionality
el_set(el, EL_HIST, history, herstory);
puts("Begin moLisp interpreter");
puts("Type 'exit' at prompt to exit");
while(keepreading){
usrin = el_gets(el, &count);
// add the command to the history, and echo it back to the user
if(count > 0){
history(herstory, &ev, H_ENTER, usrin);
if(strcmp(usrin, "exit\n"))
printf("No, You're a %s", usrin);
else{
puts("bye");
--keepreading;
}
}
}
// Clean up memory
// by freeing the memory pointed to within the structs that
// libedit has created.
history_end(herstory);
el_end(el);
return 0;
}
Notice: The instantiation of the structs that are used happens outside of
the while loop, and so do the functions that free the memory those structs are using. Because of this, I added the command to exit, otherwise I think there's a memory leak if the only way to exit the while loop is by interrupting the program. To compile:
gcc repl-macos.c -ledit -Wall -o repl-edit
-ledit is needed to link editline
If it has any relevance, I am using macOs 10.4.11
and here's my compiler, output of
gcc --version
powerpc-apple-darwin8-gcc-4.0.0 (GCC) 4.0.0 20041026 (Apple Computer, Inc. build 4061)
Now the only problem with this, and the book points this out, is that
c-code is supposed to be portable and this isn't. The next step would be to add preprocessor directives so that it uses readline on linux and editline on macos.
If you are on ubuntu add the editline library
sudo apt-get install libtedit-dev
On Debian Buster 10, I had to install the package with:
sudo apt install libeditline-dev
Instead of:
#include <editline/readline.h>
#include <editline/history.h>
I just included:
#include <editline.h>
ran the program with -leditline flag and worked perfectly.
test1.c
#include <stdio.h>
int main(void) {
printf("test\n");
delay(1000);
printf("test2\n");
}
When I try to compile...
gcc test1.c -o test1
Undefined symbols for architecture x86_64:
"_delay", referenced from:
_main in ccUnw3tY.o
ld: symbol(s) not found for architecture x86_64
collect2: ld returned 1 exit status
Certainly there is a lesson here in knowing your libraries and what linking is etc... What am I missing? I am trying to do this on OSX.
There's no delay function in C, you have to use sleep or usleep depending on what OS you're on.
What make you think there is a delay function. I dont see one in the osx docs. There is a sleep function
https://developer.apple.com/library/mac/#documentation/Darwin/Reference/ManPages/man3/sleep.3.html
An alternative of delay in C for unix os is the sleep function :
https://developer.apple.com/library/mac/documentation/Darwin/Reference/ManPages/man3/sleep.3.html
do something like :
#include <stdio.h>
#include <unistd.h>
int main(void) {
printf("test\n");
usleep(1000);
printf("test2\n");
}
If you value is for 1000 microsecondes.
The delay function works in Borland C compiler. You have to use the dos.h header file in order to use delay. Some other compilers like MinGW may not support this.
I'm getting some problems on compiling a very very simple name.c file on Mac OSX Lion.
Now, I started following Harvard CS50 course on cs50.net. I'm not totally new to programming but I was curious on how this course has been taught.
This is the source of name.c:
#include <stdio.h>
#include <cs50.h>
int
main(void)
{
printf("State your name:\n");
string name = GetString();
printf("O hai, %s!\n", name);
return 0;
}
As you can see, it requires this library: https://manual.cs50.net/CS50_Library.
Now, when I compile it, this happens:
Undefined symbols for architecture x86_64:
"_GetString", referenced from:
_main in name-vAxcar.o
ld: symbol(s) not found for architecture x86_64
clang: error: linker command failed with exit code 1 (use -v to see invocation)
make: *** [name] Error 1
If I use the same GetString() cs50.c function inside my source file, it works perfectly:
#include <stdio.h>
#include <string.h>
#include <float.h>
#include <limits.h>
#include <stdbool.h>
#include <stdlib.h>
typedef char *string;
string GetString(void);
int
main(void)
{
printf("State your name:\n");
string name = GetString();
printf("O hai, %s!\n", name);
}
string
GetString(void)
{
// CODE
}
Why does this happen?
I installed the library as it says on the link above; I checked and both cs50.h and libcs50.a are respectively in /usr/local/include and /usr/local/lib.
Thank you in advance for your help.
The problem you encounter is in the linking stage, not compiling. You did not provide the implementation of GetString, only its declaration (through the .h file you #include).
To provide the implementation itself, you usually need to link against the library which includes it; this is usually done by the -l flag to g++. For example,
g++ file.cpp -lcs50
Your second sample code does link, because you manually (and explicitly) provide an implementation for GetString, though an empty one.
I am trying to do a simple strrev on a string and I keep getting this error when I compile it on my mac
Undefined symbols for architecture x86_64:
"_strrev", referenced from:
_main in cc1zSAum.o
ld: symbol(s) not found for architecture x86_64
collect2: ld returned 1 exit status
My code is:
#include<stdio.h>
#include<stdlib.h>
#include<string.h>
int main(int argc, char *argv[]){
char str[] = "Hello world";
char * test;
test = strrev(str);
printf("%s",test);
return 0;
}
I tried playing around with the strrev line
but nothing is working
Any help would be appreciated
Thanks
There's no standard C function by that name. I did a little Googling and it looks like a few compilers and/or C library implementations have included such a function as a non-standard extension, but you can't expect any arbitrary library to have one.
Would be simple enough to write your own, though -- could be a one line loop body, even.