Re-Entrance System calls

_exit abort access alarm cfgetispeed cfgetospeed cfsetispeed cfsetospeed chdir chmod chown close creat dup dup2 execle execve exit fcntl fork fstat getegid geteuid getgid getgroups getpgrp getpid getppid getuid kill link longjmp lseek mkdir mkfifo open pathconf pause pipe read rename rmdir setgid setpgid setsid setuid sigaction sigaddset sigdelset sigemptyset sigfillset sigismember signal sigpending sigprocmask sigsuspend sleep stat sysconf tcdrain tcflow tcflush tcgetattr tcgetpgrp tcsendbreak tcsetattr tcsetpgrp time times umask uname unlink utime wait waitpid write