dyld: Library not loaded: libdb2.dylib when running GO ibm_DB sdk in MAC

[sanjeevghimire]

when running the code snippet I get this error:

I installed the driver as per the instruction in the readme. the lib folder has the file libdb2.dylib but it complains about it:

  Referenced from: /var/folders/_h/4trwzcd908g703_vdw2q1yn00000gn/T/go-
build774492263/b001/exe/db2conn
  Reason: image not found
signal: abort trap```

the code I am using is:

package main

import (
_ "github.com/ibmdb/go_ibm_db"
"database/sql"
"fmt"
)

func main(){
con:="HOSTNAME=host;DATABASE=db;PORT=50000;UID=u;PWD=pwd"
db, err:=sql.Open("go_ibm_db", con)
if err != nil{

	fmt.Println(err)
}
db.Close()

}

[sanjeevghimire]

Figured out the problem. My path was pointing to wrong DYLD library.

[bombsimon]

@akhilravuri1 I still cannot get this to work. I installed the driver with setup.go. The solution in this issue and #50 and #47 and #29 all seem to be resolved with the correct environment. Any help would be appreciated!

This is my environemnt:

$ for env in $DB2HOME $CGO_CFLAGS $CGO_LDFLAGS $DYLD_LIBRARY_PATH; do echo $env; done
/Users/simon/tmp/db2test/clidriver
-I/Users/simon/tmp/db2test/clidriver/include
-L/Users/simon/tmp/db2test/clidriver/lib
/Users/simon/tmp/db2test/clidriver/lib

When trying to use the driver, I get the error form this issue:

$ go run main.go
dyld: Library not loaded: libdb2.dylib
  Referenced from: /var/folders/q3/bf76j42160j2nt4s2tz1_fd40000gn/T/go-build982956092/b001/exe/main
  Reason: image not found
signal: abort trap

However, the file mentioned seems to be present according to me:

$ stat -f "%N (%z)" $DYLD_LIBRARY_PATH/libdb2.dylib
/Users/simon/tmp/db2test/clidriver/lib/libdb2.dylib (32902420)

What am I missing here? Why does it seem like I'm missing the library when trying to use the driver?

[bombsimon]

Ok this was new to me. Don't know what this is or why but it seems like this only occurs with go run (and the executable is being ran from a temp folder). If I compile the program first it works as expected.

$ go run main.go; echo $?                                                                                                                                                                                                                                                                                                 
dyld: Library not loaded: libdb2.dylib
  Referenced from: /var/folders/q3/bf76j42160j2nt4s2tz1_fd40000gn/T/go-build556855419/b001/exe/main
  Reason: image not found
signal: abort trap
1

$ go build main.go && ./main; echo $?
0

Is this because the driver requires a relative path? It sounds odd because libdb2.dylib isn't relative to main.go but that's the only guess I have. 🤔

[kierquebs]

Try this one

instead of:
go run main.go

I used:
go build -v

then to your command line
./project_name

[akhilravuri1]

Hi @bombsimon

please provide your mac version and go version.

Thanks,
Akhil

[bombsimon]

@kierquebs Thanks! Like I wrote in my last post in March it's working if I first build the binary and then run it so the question is why that is.

@akhilravuri1 I'm running macOS Catalina 10.15.4 with go version go1.14 darwin/amd64.

This is no major issue but I was just curious why it's possible to build and execute but not perform go run.

[robherley]

Hey I know this issue is kinda old but @bombsimon to answer your question or anyone else who finds this, the reason is here: golang/go#36572

As for the workaround, you can just use go run -exec like so:

go run -exec "env DYLD_LIBRARY_PATH=path/to/your/lib" main.go

[htdinh13]

Beside the workaround with go run -exec, do we have permanent fix for that issue?