undefined reference to 'pthread_create'
undefined reference to 'pthread_join'
问题原因:
pthread 库不是 Linux 系统默认的库,连接时需要使用静态库 libpthread.a,所以在使用pthread_create()创建线程,以及调用 pthread_atfork()函数建立fork处理程序时,需要链接该库。
问题解决:
在编译中要加 -lpthread参数
gcc thread.c -o thread -lpthread
thread.c为你些的源文件,不要忘了加上头文件#include
############################################################
# File: Makefile
#
############################################################
INSTALLDIR = $(EXEC_DIR)
INCLUDES += -I ./ -I$(PUBLIC_INCLUDE_DIR) -I ./sysctrl -I include
#INCLUDES += -I./ -I$(PUBLIC_INCLUDE_DIR) -I$(LINUXKERNEL_INSTALL_DIR)/include -I$(CMEM_INC_DIR)
CC = $(BUILD_TOOL_PREFIX)gcc $(INCLUDES) $(C_FLAGS)
CFLAGS += -Wall -O3
LDFLAGS += -s
BIN = annp
OBJS = annp.o utils.o
#LINK_TARGET = $(OBJS) $(APP_LIB_DIR)/sysctrl.a $(APP_LIB_DIR)/file_msg_drv.a
LINK_TARGET = $(APP_LIB_DIR)/file_msg_drv.a $(APP_LIB_DIR)/sysctrl.a \
LDFLAGS = -g -lpthread
SOURCES = $(wildcard *.c)
REL_OBJ = $(SOURCES:%.c=%.o)
all: $(REL_OBJ)
$(CC) $(LDFLAGS) -o $(BIN) annp.o utils.o $(LINK_TARGET) $(LDFLAGS)
REL_OBJ = $(SOURCES:%.c=%.o)
install: all
cp $(BIN) $(INSTALLDIR)
# cp -a -f lib/*.so* $(ROOT_FILE_SYS)/usr/lib/
uninstall:
rm -rf $(INSTALLDIR)/$(BIN)
clean:
rm -f $(BIN) $(BIN).{elf,gdb} $(OBJS)