CC            = gcc
CFLAGS        = -g -Wall -W
DEL_FILE      = rm -f
#include "../client/checker.h"
#include "../client/checker.o"
#include "../client/cli_utils.h"
#include "../client/cli_utils.c"

OBJECTS       = main.o
        ../client/checker.o
        ../client/cli_utils.o

default: master

master: $(OBJECTS)
    $(CC) $(CFLAGS) -o master $(OBJECTS)

main.o: main.c ../client/checker.h
        ../client/cli_utils.h
    $(CC) -c $(CFLAGS) -o main.o main.c

clean:
    -$(DEL_FILE)  master
    -$(DEL_FILE)  $(OBJECTS)

#include "../client/checker.h"
#include "../client/checker.o"
#include "../client/cli_utils.h"
#include "../client/cli_utils.c"

make -C client
make[1]: Entering directory '/home/linoukth/port/client'
gcc  -c -g -Wall -W -o main.o main.c
gcc  -c -g -Wall -W -o checker.o checker.c
gcc  -c -g -Wall -W -o cli_utils.o cli_utils.c
gcc  -g -Wall -W -o client main.o checker.o cli_utils.o
make[1]: Leaving directory '/home/linoukth/port/client'
make -C master
make[1]: Entering directory '/home/linoukth/port/master'
gcc  -c -g -Wall -W -I ../client -o main.o main.c
In file included from main.c:4:0:
../client/checker.h:37:17: error: unknown type name ‘pid_t’
 void check_fork(pid_t pid_check, int caller);
                 ^
makefile:26: recipe for target 'main.o' failed
make[1]: *** [main.o] Error 1
make[1]: Leaving directory '/home/linoukth/port/master'
makefile:10: recipe for target 'allmake' failed
make: *** [allmake] Error 2

error: unknown type name ‘pid_t’

#include <stdio.h>
#include <fcntl.h>
#include <string.h>
#include <stdlib.h>
#include <unistd.h>
#include <signal.h>
#include <sys/types.h>

#include "checker.h"