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/* POSIX test program (7). Author: Andy Tanenbaum */
/* The following POSIX calls are tested:
* pipe(), mkfifo(), fcntl()
*/
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/wait.h>
#include <errno.h>
#include <fcntl.h>
#include <limits.h>
#include <signal.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <stdio.h>
#include <setjmp.h>
#define ITERATIONS 4
int max_error = 3;
#include "common.h"
#define ITEMS 32
#define READ 10
#define WRITE 20
#define UNLOCK 30
#define U 70
#define L 80
char buf[ITEMS] = {0,1,2,3,4,5,6,7,8,9,8,7,6,5,4,3,2,1,0,1,2,3,4,5,6,7,8,9};
int subtes, xfd;
int whence = SEEK_SET, func_code = F_SETLK;
extern char **environ;
#define timed_test(func) (timed_test_func(#func, func));
int main(int argc, char *argv []);
void timed_test_func(const char *s, void (* func)(void));
void timed_test_timeout(int signum);
void test7a(void);
void test7b(void);
void test7c(void);
void test7d(void);
void test7e(void);
void test7f(void);
void test7g(void);
void test7h(void);
void test7i(void);
void test7j(void);
void cloexec_test(void);
int set(int how, int first, int last);
int locked(int b);
void sigfunc(int s);
int main(argc, argv)
int argc;
char *argv[];
{
int i, m = 0xFFFF;
if (argc == 2) m = atoi(argv[1]);
if (m == 0) cloexec_test(); /* important; do not remove this! */
start(7);
for (i = 0; i < ITERATIONS; i++) {
if (m & 00001) timed_test(test7a);
if (m & 00002) timed_test(test7b);
if (m & 00004) timed_test(test7c);
if (m & 00010) timed_test(test7d);
if (m & 00020) timed_test(test7e);
if (m & 00040) timed_test(test7f);
if (m & 00100) timed_test(test7g);
if (m & 00200) timed_test(test7h);
if (m & 00400) timed_test(test7i);
if (m & 01000) timed_test(test7j);
}
quit();
return(-1); /* impossible */
}
static jmp_buf timed_test_context;
void timed_test_timeout(int signum)
{
longjmp(timed_test_context, -1);
e(700);
quit();
exit(-1);
}
void timed_test_func(const char *s, void (* func)(void))
{
if (setjmp(timed_test_context) == 0)
{
/* the function gets 60 seconds to complete */
if (signal(SIGALRM, timed_test_timeout) == SIG_ERR) { e(701); return; }
alarm(60);
func();
alarm(0);
}
else
{
/* report timeout as error */
printf("timeout in %s\n", s);
e(702);
}
}
void test7a()
{
/* Test pipe(). */
int i, fd[2], ect;
char buf2[ITEMS+1];
/* Create a pipe, write on it, and read it back. */
subtest = 1;
if (pipe(fd) != 0) e(1);
if (write(fd[1], buf, ITEMS) != ITEMS) e(2);
buf2[0] = 0;
if (read(fd[0], buf2, ITEMS+1) != ITEMS) e(3);
ect = 0;
for (i = 0; i < ITEMS; i++) if (buf[i] != buf2[i]) ect++;
if (ect != 0) e(4);
if (close(fd[0]) != 0) e(5);
if (close(fd[1]) != 0) e(6);
/* Error test. Keep opening pipes until it fails. Check error code. */
errno = 0;
while (1) {
if (pipe(fd) < 0) break;
}
if (errno != EMFILE) e(7);
/* Close all the pipes. */
for (i = 3; i < OPEN_MAX; i++) close(i);
}
void test7b()
{
/* Test mkfifo(). */
int fdr, fdw, status;
char buf2[ITEMS+1];
int efork;
/* Create a fifo, write on it, and read it back. */
subtest = 2;
if (mkfifo("T7.b", 0777) != 0) e(1);
switch (fork()) {
case -1:
efork = errno;
printf("Fork failed: %s (%d)\n", strerror(efork), efork);
exit(1);
case 0:
/* Child reads from the fifo. */
if ( (fdr = open("T7.b", O_RDONLY)) < 0) e(5);
if (read(fdr, buf2, ITEMS+1) != ITEMS) e(6);
if (strcmp(buf, buf2) != 0) e(7);
if (close(fdr) != 0) e(8);
exit(0);
default:
/* Parent writes on the fifo. */
if ( (fdw = open("T7.b", O_WRONLY)) < 0) e(2);
if (write(fdw, buf, ITEMS) != ITEMS) e(3);
wait(&status);
if (close(fdw) != 0) e(4);
}
/* Check some error conditions. */
if (mkfifo("T7.b", 0777) != -1) e(9);
errno = 0;
if (mkfifo("a/b/c", 0777) != -1) e(10);
if (errno != ENOENT) e(11);
errno = 0;
if (mkfifo("", 0777) != -1) e(12);
if (errno != ENOENT) e(13);
errno = 0;
if (mkfifo("T7.b/x", 0777) != -1) e(14);
if (errno != ENOTDIR) e(15);
if (unlink("T7.b") != 0) e(16);
/* Now check fifos and the O_NONBLOCK flag. */
if (mkfifo("T7.b", 0600) != 0) e(17);
errno = 0;
if (open("T7.b", O_WRONLY | O_NONBLOCK) != -1) e(18);
if (errno != ENXIO) e(19);
if ( (fdr = open("T7.b", O_RDONLY | O_NONBLOCK)) < 0) e(20);
if (fork()) {
/* Parent reads from fdr. */
wait(&status); /* but first make sure writer has already run*/
if ( ( (status>>8) & 0377) != 77) e(21);
if (read(fdr, buf2, ITEMS+1) != ITEMS) e(22);
if (strcmp(buf, buf2) != 0) e(23);
if (close(fdr) != 0) e(24);
} else {
/* Child opens the fifo for writing and writes to it. */
if ( (fdw = open("T7.b", O_WRONLY | O_NONBLOCK)) < 0) e(25);
if (write(fdw, buf, ITEMS) != ITEMS) e(26);
if (close(fdw) != 0) e(27);
exit(77);
}
if (unlink("T7.b") != 0) e(28);
}
void test7c()
{
/* Test fcntl(). */
int fd, m, s, newfd, newfd2;
struct stat stat1, stat2, stat3;
subtest = 3;
errno = -100;
if ( (fd = creat("T7.c", 0777)) < 0) e(1);
/* Turn the per-file-descriptor flags on and off. */
if (fcntl(fd, F_GETFD) != 0) e(2); /* FD_CLOEXEC is initially off */
if (fcntl(fd, F_SETFD, FD_CLOEXEC) != 0) e(3);/* turn it on */
if (fcntl(fd, F_GETFD) != FD_CLOEXEC) e(4); /* should be on now */
if (fcntl(fd, F_SETFD, 0) != 0) e(5); /* turn it off */
if (fcntl(fd, F_GETFD) != 0) e(6); /* should be off now */
/* Turn the open-file-description flags on and off. Start with O_APPEND. */
m = O_WRONLY;
if (fcntl(fd, F_GETFL) != m) e(7); /* O_APPEND, O_NONBLOCK are off */
if (fcntl(fd, F_SETFL, O_APPEND) != 0) e(8); /* turn on O_APPEND */
if (fcntl(fd, F_GETFL) != (O_APPEND | m)) e(9);/* should be on now */
if (fcntl(fd, F_SETFL, 0) != 0) e(10); /* turn it off */
if (fcntl(fd, F_GETFL) != m) e(11); /* should be off now */
/* Turn the open-file-description flags on and off. Now try O_NONBLOCK. */
if (fcntl(fd, F_SETFL, O_NONBLOCK) != 0) e(12); /* turn on O_NONBLOCK */
if (fcntl(fd, F_GETFL) != (O_NONBLOCK | m)) e(13); /* should be on now */
if (fcntl(fd, F_SETFL, 0) != 0) e(14); /* turn it off */
if (fcntl(fd, F_GETFL) != m) e(15); /* should be off now */
/* Now both at once. */
if (fcntl(fd, F_SETFL, O_APPEND|O_NONBLOCK) != 0) e(16);
if (fcntl(fd, F_GETFL) != (O_NONBLOCK | O_APPEND | m)) e(17);
if (fcntl(fd, F_SETFL, 0) != 0) e(18);
if (fcntl(fd, F_GETFL) != m) e(19);
/* Now test F_DUPFD. */
if ( (newfd = fcntl(fd, F_DUPFD, 0)) != 4) e(20); /* 0-4 open */
if ( (newfd2 = fcntl(fd, F_DUPFD, 0)) != 5) e(21); /* 0-5 open */
if (close(newfd) != 0) e(22); /* 0-3, 5 open */
if ( (newfd = fcntl(fd, F_DUPFD, 0)) != 4) e(23); /* 0-5 open */
if (close(newfd) != 0) e(24); /* 0-3, 5 open */
if ( (newfd = fcntl(fd, F_DUPFD, 5)) != 6) e(25); /* 0-3, 5, 6 open */
if (close(newfd2) != 0) e(26); /* 0-3, 6 open */
/* O_APPEND should be inherited, but FD_CLOEXEC should be cleared. Check. */
if (fcntl(fd, F_SETFD, FD_CLOEXEC) != 0) e(26);/* turn FD_CLOEXEC on */
if (fcntl(fd, F_SETFL, O_APPEND) != 0) e(27); /* turn O_APPEND on */
if ( (newfd2 = fcntl(fd, F_DUPFD, 10)) != 10) e(28); /* 0-3, 6, 10 open */
if (fcntl(newfd2, F_GETFD) != 0) e(29); /* FD_CLOEXEC must be 0 */
if (fcntl(newfd2, F_GETFL) != (O_APPEND | m)) e(30); /* O_APPEND set */
if (fcntl(fd, F_SETFD, 0) != 0) e(31);/* turn FD_CLOEXEC off */
/* Check if newfd and newfd2 are the same inode. */
if (fstat(fd, &stat1) != 0) e(32);
if (fstat(fd, &stat2) != 0) e(33);
if (fstat(fd, &stat3) != 0) e(34);
if (stat1.st_dev != stat2.st_dev) e(35);
if (stat1.st_dev != stat3.st_dev) e(36);
if (stat1.st_ino != stat2.st_ino) e(37);
if (stat1.st_ino != stat3.st_ino) e(38);
/* Now check on the FD_CLOEXEC flag. Set it for fd (3) and newfd2 (10) */
if (fd != 3 || newfd2 != 10 || newfd != 6) e(39);
if (fcntl(fd, F_SETFD, FD_CLOEXEC) != 0) e(40); /* close 3 on exec */
if (fcntl(newfd2, F_SETFD, FD_CLOEXEC) != 0) e(41); /* close 10 on exec */
if (fcntl(newfd, F_SETFD, 0) != 0) e(42); /* don't close 6 */
if (fork()) {
wait(&s); /* parent just waits */
if (WEXITSTATUS(s) != 0) e(43);
} else {
execle("../test7", "test7", "0", (char *) 0, environ);
exit(1); /* the impossible never happens, right? */
}
/* Finally, close all the files. */
if (fcntl(fd, F_SETFD, 0) != 0) e(44); /* FD_CLOEXEC off */
if (fcntl(newfd2, F_SETFD, 0) != 0) e(45); /* FD_CLOEXEC off */
if (close(fd) != 0) e(46);
if (close(newfd) != 0) e(47);
if (close(newfd2) != 0) e(48);
}
void test7d()
{
/* Test file locking. */
subtest = 4;
if ( (xfd = creat("T7.d", 0777)) != 3) e(1);
close(xfd);
if ( (xfd = open("T7.d", O_RDWR)) < 0) e(2);
if (write(xfd, buf, ITEMS) != ITEMS) e(3);
if (set(WRITE, 0, 3) != 0) e(4);
if (set(WRITE, 5, 9) != 0) e(5);
if (set(UNLOCK, 0, 3) != 0) e(6);
if (set(UNLOCK, 4, 9) != 0) e(7);
if (set(READ, 1, 4) != 0) e(8);
if (set(READ, 4, 7) != 0) e(9);
if (set(UNLOCK, 4, 7) != 0) e(10);
if (set(UNLOCK, 1, 4) != 0) e(11);
if (set(WRITE, 0, 3) != 0) e(12);
if (set(WRITE, 5, 7) != 0) e(13);
if (set(WRITE, 9 ,10) != 0) e(14);
if (set(UNLOCK, 0, 4) != 0) e(15);
if (set(UNLOCK, 0, 7) != 0) e(16);
if (set(UNLOCK, 0, 2000) != 0) e(17);
if (set(WRITE, 0, 3) != 0) e(18);
if (set(WRITE, 5, 7) != 0) e(19);
if (set(WRITE, 9 ,10) != 0) e(20);
if (set(UNLOCK, 0, 100) != 0) e(21);
if (set(WRITE, 0, 9) != 0) e(22);
if (set(UNLOCK, 8, 9) != 0) e(23);
if (set(UNLOCK, 0, 2) != 0) e(24);
if (set(UNLOCK, 5, 5) != 0) e(25);
if (set(UNLOCK, 4, 6) != 0) e(26);
if (set(UNLOCK, 3, 3) != 0) e(27);
if (set(UNLOCK, 7, 7) != 0) e(28);
if (set(WRITE, 0, 10) != 0) e(29);
if (set(UNLOCK, 0, 1000) != 0) e(30);
/* Up until now, all locks have been disjoint. Now try conflicts. */
if (set(WRITE, 0, 4) != 0) e(31);
if (set(WRITE, 4, 7) != 0) e(32); /* owner may lock same byte twice */
if (set(WRITE, 5, 10) != 0) e(33);
if (set(UNLOCK, 0, 11) != 0) e(34);
/* File is now unlocked. Length 0 means whole file. */
if (set(WRITE, 2, 1) != 0) e(35); /* this locks whole file */
if (set(WRITE, 9,10) != 0) e(36); /* a process can relock its file */
if (set(WRITE, 3, 3) != 0) e(37);
if (set(UNLOCK, 0, -1) != 0) e(38); /* file is now unlocked. */
/* Test F_GETLK. */
if (set(WRITE, 2, 3) != 0) e(39);
if (locked(1) != U) e(40);
if (locked(2) != L) e(41);
if (locked(3) != L) e(42);
if (locked(4) != U) e(43);
if (set(UNLOCK, 2, 3) != 0) e(44);
if (locked(2) != U) e(45);
if (locked(3) != U) e(46);
close(xfd);
}
void test7e()
{
/* Test to see if SETLKW blocks as it should. */
int pid, s;
subtest = 5;
if ( (xfd = creat("T7.e", 0777)) != 3) e(1);
if (close(xfd) != 0) e(2);
if ( (xfd = open("T7.e", O_RDWR)) < 0) e(3);
if (write(xfd, buf, ITEMS) != ITEMS) e(4);
if (set(WRITE, 0, 3) != 0) e(5);
if ( (pid = fork()) ) {
/* Parent waits until child has started before signaling it. */
while (access("T7.e1", 0) != 0) ;
unlink("T7.e1");
sleep(1);
if (kill(pid, SIGKILL) < 0) e(6);
if (wait(&s) != pid) e(7);
} else {
/* Child tries to lock and should block. */
if (creat("T7.e1", 0777) < 0) e(8);
func_code = F_SETLKW;
if (set(WRITE, 0, 3) != 0) e(9); /* should block */
errno = -1000;
e(10); /* process should be killed by signal */
exit(0); /* should never happen */
}
close(xfd);
}
void test7f()
{
/* Test to see if SETLKW gives EINTR when interrupted. */
int pid, s;
subtest = 6;
if ( (xfd = creat("T7.f", 0777)) != 3) e(1);
if (close(xfd) != 0) e(2);
if ( (xfd = open("T7.f", O_RDWR)) < 0) e(3);
if (write(xfd, buf, ITEMS) != ITEMS) e(4);
if (set(WRITE, 0, 3) != 0) e(5);
if ( (pid = fork()) ) {
/* Parent waits until child has started before signaling it. */
while (access("T7.f1", 0) != 0) ;
unlink("T7.f1");
sleep(1);
if (kill(pid, SIGTERM) < 0) e(6);
if (wait(&s) != pid) e(7);
if ( (s>>8) != 19) e(8);
} else {
/* Child tries to lock and should block.
* `signal(SIGTERM, sigfunc);' to set the signal handler is inadequate
* because on systems like BSD the sigaction flags for signal include
* `SA_RESTART' so syscalls are restarted after they have been
* interrupted by a signal.
*/
struct sigaction sa, osa;
sa.sa_handler = sigfunc;
sigemptyset(&sa.sa_mask);
sa.sa_flags = 0;
if (sigaction(SIGTERM, &sa, &osa) < 0) e(999);
if (creat("T7.f1", 0777) < 0) e(9);
func_code = F_SETLKW;
if (set(WRITE, 0, 3) != -1) e(10); /* should block */
if (errno != EINTR) e(11); /* signal should release it */
exit(19);
}
close(xfd);
}
void test7g()
{
/* Test to see if SETLKW unlocks when the needed lock becomes available. */
int pid, s;
subtest = 7;
if ( (xfd = creat("T7.g", 0777)) != 3) e(1);
if (close(xfd) != 0) e(2);
if ( (xfd = open("T7.g", O_RDWR)) < 0) e(3);
if (write(xfd, buf, ITEMS) != ITEMS) e(4);
if (set(WRITE, 0, 3) != 0) e(5); /* bytes 0 to 3 are now locked */
if ( (pid = fork()) ) {
/* Parent waits for child to start. */
while (access("T7.g1", 0) != 0) ;
unlink("T7.g1");
sleep(1);
if (set(UNLOCK, 0, 3) != 0) e(5);
if (wait(&s) != pid) e(6);
if ( (s >> 8) != 29) e(7);
} else {
/* Child tells parent it is alive, then tries to lock and is blocked.*/
func_code = F_SETLKW;
if (creat("T7.g1", 0777) < 0) e(8);
if (set(WRITE, 3, 3) != 0) e(9); /* process must block now */
if (set(UNLOCK, 3, 3) != 0) e(10);
exit(29);
}
close(xfd);
}
void test7h()
{
/* Test to see what happens if two processed block on the same lock. */
int pid, pid2, s, w;
subtest = 8;
if ( (xfd = creat("T7.h", 0777)) != 3) e(1);
if (close(xfd) != 0) e(2);
if ( (xfd = open("T7.h", O_RDWR)) < 0) e(3);
if (write(xfd, buf, ITEMS) != ITEMS) e(4);
if (set(WRITE, 0, 3) != 0) e(5); /* bytes 0 to 3 are now locked */
if ( (pid = fork()) ) {
if ( (pid2 = fork()) ) {
/* Parent waits for child to start. */
while (access("T7.h1", 0) != 0) ;
while (access("T7.h2", 0) != 0) ;
unlink("T7.h1");
unlink("T7.h2");
sleep(1);
if (set(UNLOCK, 0, 3) != 0) e(6);
w = wait(&s);
if (w != pid && w != pid2) e(7);
s = s >> 8;
if (s != 39 && s != 49) e(8);
w = wait(&s);
if (w != pid && w != pid2) e(9);
s = s >> 8;
if (s != 39 && s != 49) e(10);
} else {
func_code = F_SETLKW;
if (creat("T7.h1", 0777) < 0) e(11);
if (set(WRITE, 0, 0) != 0) e(12); /* block now */
if (set(UNLOCK, 0, 0) != 0) e(13);
exit(39);
}
} else {
/* Child tells parent it is alive, then tries to lock and is blocked.*/
func_code = F_SETLKW;
if (creat("T7.h2", 0777) < 0) e(14);
if (set(WRITE, 0, 1) != 0) e(15); /* process must block now */
if (set(UNLOCK, 0, 1) != 0) e(16);
exit(49);
}
close(xfd);
}
void test7i()
{
/* Check error conditions for fcntl(). */
int tfd, i;
subtest = 9;
errno = 0;
if ( (xfd = creat("T7.i", 0777)) != 3) e(1);
if (close(xfd) != 0) e(2);
if ( (xfd = open("T7.i", O_RDWR)) < 0) e(3);
if (write(xfd, buf, ITEMS) != ITEMS) e(4);
if (set(WRITE, 0, 3) != 0) e(5); /* bytes 0 to 3 are now locked */
if (set(WRITE, 0, 0) != 0) e(6);
if (errno != 0) e(7);
errno = 0;
if (set(WRITE, 3, 3) != 0) e(8);
if (errno != 0) e(9);
tfd = xfd; /* hold good value */
xfd = -99;
errno = 0;
if (set(WRITE, 0, 0) != -1) e(10);
if (errno != EBADF) e(11);
errno = 0;
if ( (xfd = open("T7.i", O_WRONLY)) < 0) e(12);
if (set(READ, 0, 0) != -1) e(13);
if (errno != EBADF) e(14);
if (close(xfd) != 0) e(15);
errno = 0;
if ( (xfd = open("T7.i", O_RDONLY)) < 0) e(16);
if (set(WRITE, 0, 0) != -1) e(17);
if (errno != EBADF) e(18);
if (close(xfd) != 0) e(19);
xfd = tfd; /* restore legal xfd value */
/* Check for EINVAL. */
errno = 0;
if (fcntl(xfd, F_DUPFD, OPEN_MAX) != -1) e(20);
if (errno != EINVAL) e(21);
errno = 0;
if (fcntl(xfd, F_DUPFD, -1) != -1) e(22);
if (errno != EINVAL) e(23);
xfd = 0; /* stdin does not support locking */
errno = 0;
if (set(READ, 0, 0) != -1) e(24);
if (errno != EINVAL) e(25);
xfd = tfd;
/* Check ENOLCK. */
for (i = 0; i < ITEMS; i++) {
if (set(WRITE, i, i) == 0) continue;
if (errno != ENOLCK) {
e(26);
break;
}
}
/* Check EMFILE. */
for (i = xfd + 1; i < OPEN_MAX; i++) open("T7.i", 0); /* use up all fds */
errno = 0;
if (fcntl(xfd, F_DUPFD, 0) != -1) e(27); /* No fds left */
if (errno != EMFILE) e(28);
for (i = xfd; i < OPEN_MAX; i++) if (close(i) != 0) e(29);
}
void test7j()
{
/* Test file locking with two processes. */
int s;
subtest = 10;
if ( (xfd = creat("T7.j", 0777)) != 3) e(1);
close(xfd);
if ( (xfd = open("T7.j", O_RDWR)) < 0) e(2);
if (write(xfd, buf, ITEMS) != ITEMS) e(3);
if (set(WRITE, 0, 4) != 0) e(4); /* lock belongs to parent */
if (set(READ, 10, 16) != 0) e(5); /* lock belongs to parent */
/* Up until now, all locks have been disjoint. Now try conflicts. */
if (fork()) {
/* Parent just waits for child to finish. */
wait(&s);
} else {
/* Child does the testing. */
errno = -100;
if (set(WRITE, 5, 7) < 0) e(6); /* should work */
if (set(WRITE, 4, 7) >= 0) e(7); /* child may not lock byte 4 */
if (errno != EACCES && errno != EAGAIN) e(8);
if (set(WRITE, 5, 9) != 0) e(9);
if (set(UNLOCK, 5, 9) != 0) e(10);
if (set(READ, 9, 17) < 0) e(11); /* shared READ lock is ok */
exit(0);
}
close(xfd);
}
void cloexec_test()
{
/* To text whether the FD_CLOEXEC flag actually causes files to be
* closed upon exec, we have to exec something. The test is carried
* out by forking, and then having the child exec test7 itself, but
* with argument 0. This is detected, and control comes here.
* File descriptors 3 and 10 should be closed here, and 10 open.
*/
if (close(3) == 0) e(1001); /* close should fail; it was closed on exec */
if (close(6) != 0) e(1002); /* close should succeed */
if (close(10) == 0) e(1003); /* close should fail */
fflush(stdout);
exit(0);
}
int set(how, first, last)
int how, first, last;
{
int r;
struct flock flock;
if (how == READ) flock.l_type = F_RDLCK;
if (how == WRITE) flock.l_type = F_WRLCK;
if (how == UNLOCK) flock.l_type = F_UNLCK;
flock.l_whence = whence;
flock.l_start = (long) first;
flock.l_len = (long) last - (long) first + 1;
r = fcntl(xfd, func_code, &flock);
if (r != -1)
return(0);
else
return(-1);
}
int locked(b)
int b;
/* Test to see if byte b is locked. Return L or U */
{
struct flock flock;
pid_t pid;
int status;
flock.l_type = F_WRLCK;
flock.l_whence = whence;
flock.l_start = (long) b;
flock.l_len = 1;
/* Process' own locks are invisible to F_GETLK, so fork a child to test. */
pid = fork();
if (pid == 0) {
if (fcntl(xfd, F_GETLK, &flock) != 0) e(2000);
exit(flock.l_type == F_UNLCK ? U : L);
}
if (pid == -1) e(2001);
if (fcntl(xfd, F_GETLK, &flock) != 0) e(2002);
if (flock.l_type != F_UNLCK) e(2003);
if (wait(&status) != pid) e(2004);
if (!WIFEXITED(status)) e(2005);
return(WEXITSTATUS(status));
}
void sigfunc(s)
int s; /* for ANSI */
{
}