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Compilation / link error using pthread

I am trying to create a small program that sorts an array using threads, but I cannot get it to compile with thread support.

Error:

sortieren.c:(.text+0xd7): undefined reference to `ptread_create'

I used the make file for easy compilation, but also on the command line. I can not make it work.

Base Code:

 #include <pthread.h> int main(int argc, char **argv) { pthread_t threads[2]; // code snipped int ret = ptread_create(&threads[0], NULL, threadOne(), NULL); printf("ret: %d\n", ret); // code snipped }

Make file:

 sortieren : sortieren.o gcc sortieren.o sortieren.o : sortieren.c gcc -pthread -c sortieren.c

Using make sortieren leads to this conclusion

 gcc -pthread -c sortieren.c gcc sortieren.o sortieren.o: In function `main': sortieren.c:(.text+0xd7): undefined reference to `ptread_create' collect2: ld returned 1 exit status make: *** [sortieren] Fehler 1

Of course, I tried google, but every “solution” I found did not work for me. I tried -pthread or -lpthread everywhere in my makefile. To make sure I did nothing wrong with my code, I also tried a publicly available sample :

 #include <pthread.h> #include <stdio.h> #include <stdlib.h> #define NUM_THREADS 5 void *PrintHello(void *threadid) { long tid; tid = (long)threadid; printf("Hello World! It me, thread #%ld!\n", tid); pthread_exit(NULL); } int main(int argc, char *argv[]) { pthread_t threads[NUM_THREADS]; int rc; long t; for(t=0;t<NUM_THREADS;t++){ printf("In main: creating thread %ld\n", t); rc = pthread_create(&threads[t], NULL, PrintHello, (void *)t); if (rc){ printf("ERROR; return code from pthread_create() is %d\n", rc); exit(-1); } } pthread_exit(NULL); }

The error is there.

System: Ubuntu 11.04 64bit, GCC version 4.5.2

 Using built-in specs. COLLECT_GCC=gcc COLLECT_LTO_WRAPPER=/usr/lib/x86_64-linux-gnu/gcc/x86_64-linux-gnu/4.5.2/lto-wrapper Target: x86_64-linux-gnu Configured with: ../src/configure -v --with-pkgversion='Ubuntu/Linaro 4.5.2-8ubuntu4' --with-bugurl=file:///usr/share/doc/gcc-4.5/README.Bugs --enable-languages=c,c++,fortran,objc,obj-c++ --prefix=/usr --program-suffix=-4.5 --enable-shared --enable-multiarch --with-multiarch-defaults=x86_64-linux-gnu --enable-linker-build-id --with-system-zlib --libexecdir=/usr/lib/x86_64-linux-gnu --without-included-gettext --enable-threads=posix --with-gxx-include-dir=/usr/include/c++/4.5 --libdir=/usr/lib/x86_64-linux-gnu --enable-nls --with-sysroot=/ --enable-clocale=gnu --enable-libstdcxx-debug --enable-libstdcxx-time=yes --enable-plugin --enable-gold --enable-ld=default --with-plugin-ld=ld.gold --enable-objc-gc --disable-werror --with-arch-32=i686 --with-tune=generic --enable-checking=release --build=x86_64-linux-gnu --host=x86_64-linux-gnu --target=x86_64-linux-gnu Thread model: posix gcc version 4.5.2 (Ubuntu/Linaro 4.5.2-8ubuntu4)

Update

Using what @Banthar is talking about doesn't work either.

 $ make sortieren gcc -c sortieren.c gcc -lpthread sortieren.o sortieren.o: In function `main': sortieren.c:(.text+0xd7): undefined reference to `ptread_create' collect2: ld returned 1 exit status make: *** [sortieren] Fehler 1
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2 answers
 sortieren : sortieren.o gcc sortieren.o sortieren.o : sortieren.c gcc -pthread -c sortieren.c

Must be:

 sortieren : sortieren.o gcc -lpthread sortieren.o sortieren.o : sortieren.c gcc -c sortieren.c
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Your spelling is incorrect in its pthread_create() , and I think you are writing ptread_create() . At least your error says this: undefined reference to ptread_create

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