diff --git a/libc/SYSCALLS.TXT b/libc/SYSCALLS.TXT
index 6f12be87f..26673e61a 100644
--- a/libc/SYSCALLS.TXT
+++ b/libc/SYSCALLS.TXT
@@ -62,6 +62,7 @@ int     getgroups:getgroups32(int, gid_t *)    205,205,-1
 int     getgroups:getgroups(int, gid_t *)      -1,-1,80
 pid_t   getpgid(pid_t)             132
 pid_t   getppid()                  64
+pid_t   getsid(pid_t)              147
 pid_t   setsid()                   66
 int     setgid:setgid32(gid_t)     214,214,-1
 int     setgid:setgid(gid_t)       -1,-1,46
diff --git a/libc/arch-arm/syscalls.mk b/libc/arch-arm/syscalls.mk
index b1c669df8..565c2bdfb 100644
--- a/libc/arch-arm/syscalls.mk
+++ b/libc/arch-arm/syscalls.mk
@@ -18,6 +18,7 @@ syscall_src += arch-arm/syscalls/readahead.S
 syscall_src += arch-arm/syscalls/getgroups.S
 syscall_src += arch-arm/syscalls/getpgid.S
 syscall_src += arch-arm/syscalls/getppid.S
+syscall_src += arch-arm/syscalls/getsid.S
 syscall_src += arch-arm/syscalls/setsid.S
 syscall_src += arch-arm/syscalls/setgid.S
 syscall_src += arch-arm/syscalls/__setreuid.S
diff --git a/libc/arch-arm/syscalls/getsid.S b/libc/arch-arm/syscalls/getsid.S
new file mode 100644
index 000000000..856d41a5c
--- /dev/null
+++ b/libc/arch-arm/syscalls/getsid.S
@@ -0,0 +1,14 @@
+/* autogenerated by gensyscalls.py */
+#include <machine/asm.h>
+#include <sys/linux-syscalls.h>
+
+ENTRY(getsid)
+    .save   {r4, r7}
+    stmfd   sp!, {r4, r7}
+    ldr     r7, =__NR_getsid
+    swi     #0
+    ldmfd   sp!, {r4, r7}
+    movs    r0, r0
+    bxpl    lr
+    b       __set_syscall_errno
+END(getsid)
diff --git a/libc/arch-mips/syscalls.mk b/libc/arch-mips/syscalls.mk
index 6de0c8fb0..51fd32df5 100644
--- a/libc/arch-mips/syscalls.mk
+++ b/libc/arch-mips/syscalls.mk
@@ -19,6 +19,7 @@ syscall_src += arch-mips/syscalls/readahead.S
 syscall_src += arch-mips/syscalls/getgroups.S
 syscall_src += arch-mips/syscalls/getpgid.S
 syscall_src += arch-mips/syscalls/getppid.S
+syscall_src += arch-mips/syscalls/getsid.S
 syscall_src += arch-mips/syscalls/setsid.S
 syscall_src += arch-mips/syscalls/setgid.S
 syscall_src += arch-mips/syscalls/__setreuid.S
diff --git a/libc/arch-mips/syscalls/getsid.S b/libc/arch-mips/syscalls/getsid.S
new file mode 100644
index 000000000..2c089acc4
--- /dev/null
+++ b/libc/arch-mips/syscalls/getsid.S
@@ -0,0 +1,22 @@
+/* autogenerated by gensyscalls.py */
+#include <sys/linux-syscalls.h>
+    .text
+    .globl getsid
+    .align 4
+    .ent getsid
+
+getsid:
+    .set noreorder
+    .cpload $t9
+    li $v0, __NR_getsid
+    syscall
+    bnez $a3, 1f
+    move $a0, $v0
+    j $ra
+    nop
+1:
+    la $t9,__set_errno
+    j $t9
+    nop
+    .set reorder
+    .end getsid
diff --git a/libc/arch-x86/syscalls.mk b/libc/arch-x86/syscalls.mk
index 235222160..623c19365 100644
--- a/libc/arch-x86/syscalls.mk
+++ b/libc/arch-x86/syscalls.mk
@@ -19,6 +19,7 @@ syscall_src += arch-x86/syscalls/readahead.S
 syscall_src += arch-x86/syscalls/getgroups.S
 syscall_src += arch-x86/syscalls/getpgid.S
 syscall_src += arch-x86/syscalls/getppid.S
+syscall_src += arch-x86/syscalls/getsid.S
 syscall_src += arch-x86/syscalls/setsid.S
 syscall_src += arch-x86/syscalls/setgid.S
 syscall_src += arch-x86/syscalls/__setreuid.S
diff --git a/libc/arch-x86/syscalls/getsid.S b/libc/arch-x86/syscalls/getsid.S
new file mode 100644
index 000000000..7046b9a01
--- /dev/null
+++ b/libc/arch-x86/syscalls/getsid.S
@@ -0,0 +1,23 @@
+/* autogenerated by gensyscalls.py */
+#include <sys/linux-syscalls.h>
+
+    .text
+    .type getsid, @function
+    .globl getsid
+    .align 4
+
+getsid:
+    pushl   %ebx
+    mov     8(%esp), %ebx
+    movl    $__NR_getsid, %eax
+    int     $0x80
+    cmpl    $-129, %eax
+    jb      1f
+    negl    %eax
+    pushl   %eax
+    call    __set_errno
+    addl    $4, %esp
+    orl     $-1, %eax
+1:
+    popl    %ebx
+    ret
diff --git a/libc/include/sys/linux-syscalls.h b/libc/include/sys/linux-syscalls.h
index 48564cd39..056829303 100644
--- a/libc/include/sys/linux-syscalls.h
+++ b/libc/include/sys/linux-syscalls.h
@@ -83,6 +83,7 @@
 #define __NR_msync                        (__NR_SYSCALL_BASE + 144)
 #define __NR_readv                        (__NR_SYSCALL_BASE + 145)
 #define __NR_writev                       (__NR_SYSCALL_BASE + 146)
+#define __NR_getsid                       (__NR_SYSCALL_BASE + 147)
 #define __NR_perf_event_open              (__NR_SYSCALL_BASE + 364)
 
 #ifdef __arm__
diff --git a/libc/include/unistd.h b/libc/include/unistd.h
index d8263fef6..a6a6dbf6f 100644
--- a/libc/include/unistd.h
+++ b/libc/include/unistd.h
@@ -60,6 +60,7 @@ extern int    setpgid(pid_t, pid_t);
 extern pid_t  getppid(void);
 extern pid_t  getpgrp(void);
 extern int    setpgrp(void);
+extern pid_t  getsid(pid_t);
 extern pid_t  setsid(void);
 
 extern int execv(const char *, char * const *);
@@ -192,7 +193,6 @@ extern pid_t tcgetpgrp(int fd);
 extern int   tcsetpgrp(int fd, pid_t _pid);
 
 #if 0 /* MISSING FROM BIONIC */
-extern pid_t  getsid(pid_t);
 extern int execvpe(const char *, char * const *, char * const *);
 extern int execlpe(const char *, const char *, ...);
 extern int getfsuid(uid_t);