gdb/testsuite/gdb.base/foll-fork.exp - binutils-gdb - Git at Google

 #   Copyright 1997-2020 Free Software Foundation, Inc.

 # This program is free software; you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by
 # the Free Software Foundation; either version 3 of the License, or
 # (at your option) any later version.
 #
 # This program is distributed in the hope that it will be useful,
 # but WITHOUT ANY WARRANTY; without even the implied warranty of
 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 # GNU General Public License for more details.
 #
 # You should have received a copy of the GNU General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.

 # Until "set follow-fork-mode" and "catch fork" are implemented on
 # other targets...
 #
 if { ![istarget "*-*-linux*"] && ![istarget "*-*-openbsd*"] } then {
     continue
 }

 # Test relies on checking follow-fork output. Do not run if gdb debug is
 # enabled as it will be redirected to the log.
 if [gdb_debug_enabled] {
     untested "debug is enabled"
     return 0
 }

 standard_testfile

 if {[prepare_for_testing "failed to prepare" $testfile $srcfile debug]} {
     return -1
 }

 proc check_fork_catchpoints {} {
   global gdb_prompt

   # Verify that the system supports "catch fork".
   gdb_test "catch fork" "Catchpoint \[0-9\]* \\(fork\\)" "insert first fork catchpoint"
   set has_fork_catchpoints 0
   gdb_test_multiple "continue" "continue to first fork catchpoint" {
     -re ".*Your system does not support this type\r\nof catchpoint.*$gdb_prompt $" {
       unsupported "continue to first fork catchpoint"
     }
     -re ".*Catchpoint.*$gdb_prompt $" {
       set has_fork_catchpoints 1
       pass "continue to first fork catchpoint"
     }
   }

   if {$has_fork_catchpoints == 0} {
     unsupported "fork catchpoints"
     return -code return
   }
 }

 # Test follow-fork to ensure that the correct process is followed, that
 # the followed process stops where it is expected to stop, that processes
 # are detached (or not) as expected, and that the inferior list has the
 # expected contents after following the fork.  WHO is the argument to
 # the 'set follow-fork-mode' command, DETACH is the argument to the
 # 'set detach-on-fork' command, and CMD is the GDB command used to
 # execute the program past the fork.  If the value of WHO or DETACH is
 # 'default', the corresponding GDB command is skipped for that test.
 # The value of CMD must be either 'next 2' or 'continue'.
 proc test_follow_fork { who detach cmd } {
     global gdb_prompt
     global srcfile
     global testfile

     with_test_prefix "follow $who, detach $detach, command \"$cmd\"" {

 	# Start a new debugger session each time so defaults are legitimate.
 	clean_restart $testfile

 	if ![runto_main] {
 	    untested "could not run to main"
 	    return -1
 	}

 	# The "Detaching..." and "Attaching..." messages may be hidden by
 	# default.
 	gdb_test_no_output "set verbose"

 	# Set follow-fork-mode if we aren't using the default.
 	if {$who == "default"} {
 	    set who "parent"
 	} else {
 	    gdb_test_no_output "set follow-fork $who"
 	}

 	gdb_test "show follow-fork" \
 	"Debugger response to a program call of fork or vfork is \"$who\"."

 	# Set detach-on-fork mode if we aren't using the default.
 	if {$detach == "default"} {
 	    set detach "on"
 	} else {
 	    gdb_test_no_output "set detach-on-fork $detach"
 	}

 	gdb_test "show detach-on-fork" \
 		 "Whether gdb will detach.* fork is $detach."

 	# Set a breakpoint after the fork if we aren't single-stepping
 	# past the fork.
 	if {$cmd == "continue"} {
 	    set bp_after_fork [gdb_get_line_number "set breakpoint here"]
 	    gdb_test "break ${srcfile}:$bp_after_fork" \
 		     "Breakpoint.*, line $bp_after_fork.*" \
 		     "set breakpoint after fork"
 	}

 	# Set up the output we expect to see after we run.
 	set expected_re ""
 	if {$who == "child"} {
 	    set expected_re "\\\[Attaching after.* fork to.*"
 	    if {$detach == "on"} {
 		append expected_re "\\\[Detaching after fork from .*"
 	    }
 	    append expected_re "set breakpoint here.*"
 	} elseif {$who == "parent" && $detach == "on"} {
 	    set expected_re "\\\[Detaching after fork from .*set breakpoint here.*"
 	} else {
 	    set expected_re ".*set breakpoint here.*"
 	}

 	# Test running past and following the fork, using the parameters
 	# set above.
 	gdb_test $cmd $expected_re "$cmd past fork"

 	# Check that we have the inferiors arranged correctly after
 	# following the fork.
 	set resume_unfollowed 0
 	if {$who == "parent" && $detach == "on"} {

 	    # Follow parent / detach child: the only inferior is the parent.
 	    gdb_test "info inferiors" "\\* 1 .* process.*"

 	} elseif {$who == "parent" && $detach == "off"} {

 	    # Follow parent / keep child: two inferiors under debug, the
 	    # parent is the current inferior.
 	    gdb_test "info inferiors" "\\* 1 .*process.* 2 .*process.*"

 	    gdb_test "inferior 2" "Switching to inferior 2 .*"
 	    set resume_unfollowed 1

 	} elseif {$who == "child" && $detach == "on"} {

 	    # Follow child / detach parent: the child is under debug and is
 	    # the current inferior.  The parent is listed but is not under
 	    # debug.
 	    gdb_test "info inferiors" " 1 .*<null>.*\\* 2 .*process.*"

 	} elseif {$who == "child" && $detach == "off"} {

 	    # Follow child / keep parent: two inferiors under debug, the
 	    # child is the current inferior.
 	    gdb_test "info inferiors" " 1 .*process.*\\* 2 .*process.*"

 	    gdb_test "inferior 1" "Switching to inferior 1 .*"
 	    set resume_unfollowed 1
 	}

 	if {$resume_unfollowed == 1} {
 	    if {$cmd == "next 2"} {

 		gdb_continue_to_end "continue unfollowed inferior to end"

 	    } elseif {$cmd == "continue"} {

 		gdb_continue_to_breakpoint \
 		    "continue unfollowed inferior to bp" \
 		    ".* set breakpoint here.*"
 	    }
 	}
     }
 }

 proc catch_fork_child_follow {} {
     global gdb_prompt
     global srcfile

     set bp_after_fork [gdb_get_line_number "set breakpoint here"]

     gdb_test "catch fork" "Catchpoint \[0-9\]* \\(fork\\)" \
 	"explicit child follow, set catch fork"

     # Verify that the catchpoint is mentioned in an "info breakpoints",
     # and further that the catchpoint mentions no process id.
     #
     set test_name "info shows catchpoint without pid"
     gdb_test_multiple "info breakpoints" "$test_name" {
 	-re ".*catchpoint.*keep y.*fork\[\r\n\]+$gdb_prompt $" {
 	    pass "$test_name"
 	}
     }

     gdb_test "continue" \
 	"Catchpoint \[0-9\]* \\(forked process \[0-9\]*\\),.*" \
 	"explicit child follow, catch fork"

     # Verify that the catchpoint is mentioned in an "info breakpoints",
     # and further that the catchpoint managed to capture a process id.
     #
     set test_name "info shows catchpoint without pid"
     gdb_test_multiple "info breakpoints" "$test_name" {
 	-re ".*catchpoint.*keep y.*fork, process.*$gdb_prompt $" {
 	    pass "$test_name"
 	}
     }

     gdb_test_no_output "set follow-fork child"

     gdb_test "tbreak ${srcfile}:$bp_after_fork" \
 	"Temporary breakpoint.*, line $bp_after_fork.*" \
 	"set follow-fork child, tbreak"

     set expected_re "\\\[Attaching after.* fork to.*\\\[Detaching after fork from"
     append expected_re ".* at .*$bp_after_fork.*"
     gdb_test "continue" $expected_re "set follow-fork child, hit tbreak"

     # The parent has been detached; allow time for any output it might
     # generate to arrive, so that output doesn't get confused with
     # any expected debugger output from a subsequent testpoint.
     #
     exec sleep 1

     gdb_test "delete breakpoints" \
 	"" \
 	"set follow-fork child, cleanup" \
 	"Delete all breakpoints. \\(y or n\\) $" \
 	"y"
 }

 proc catch_fork_unpatch_child {} {
     global gdb_prompt
     global srcfile

     set bp_exit [gdb_get_line_number "at exit"]

     gdb_test "break callee" "file .*$srcfile, line .*" \
 	"unpatch child, break at callee"
     gdb_test "catch fork" "Catchpoint \[0-9\]* \\(fork\\)" \
 	"unpatch child, set catch fork"

     gdb_test "continue" \
 	"Catchpoint \[0-9\]* \\(forked process \[0-9\]*\\),.*" \
 	"unpatch child, catch fork"

     # Delete all breakpoints and catchpoints.
     delete_breakpoints

     # Force $srcfile as the current GDB source can be in glibc sourcetree.
     gdb_test "break $srcfile:$bp_exit" \
 	"Breakpoint .*file .*$srcfile, line .*" \
 	"unpatch child, breakpoint at exit call"

     gdb_test_no_output "set follow-fork child" \
 	"unpatch child, set follow-fork child"

     set test "unpatch child, unpatched parent breakpoints from child"
     gdb_test_multiple "continue" $test {
 	-re "at exit.*$gdb_prompt $" {
 	    pass "$test"
 	}
 	-re "SIGTRAP.*$gdb_prompt $" {
 	    fail "$test"

 	    # Explicitly kill this child, so we can continue gracefully
 	    # with further testing...
 	    send_gdb "kill\n"
 	    gdb_expect {
 		-re ".*Kill the program being debugged.*y or n. $" {
 		    send_gdb "y\n"
 		    gdb_expect -re "$gdb_prompt $" {}
 		}
 	    }
 	}
     }
 }

 proc tcatch_fork_parent_follow {} {
     global gdb_prompt
     global srcfile

     set bp_after_fork [gdb_get_line_number "set breakpoint here"]

     gdb_test "catch fork" "Catchpoint \[0-9\]* \\(fork\\)" \
 	"explicit parent follow, set tcatch fork"

 # ??rehrauer: I don't yet know how to get the id of the tcatch
 # via this script, so that I can add a -do list to it.  For now,
 # do the follow stuff after the catch happens.

     gdb_test "continue" \
 	"Catchpoint \[0-9\]* \\(forked process \[0-9\]*\\),.*" \
 	"explicit parent follow, tcatch fork"

     gdb_test_no_output "set follow-fork parent"

     gdb_test "tbreak ${srcfile}:$bp_after_fork" \
 	"Temporary breakpoint.*, line $bp_after_fork.*" \
 	"set follow-fork parent, tbreak"

     gdb_test "continue" \
 	"\\\[Detaching after fork from.* at .*$bp_after_fork.*" \
 	"set follow-fork parent, hit tbreak"

     # The child has been detached; allow time for any output it might
     # generate to arrive, so that output doesn't get confused with
     # any expected debugger output from a subsequent testpoint.
     #
     exec sleep 1

     gdb_test "delete breakpoints" \
 	"" \
 	"set follow-fork parent, cleanup" \
 	"Delete all breakpoints. \\(y or n\\) $" \
 	"y"
 }

 proc do_fork_tests {} {
     global gdb_prompt
     global testfile

     # Verify that help is available for "set follow-fork-mode".
     #
     gdb_test "help set follow-fork-mode" \
 	"Set debugger response to a program call of fork or vfork..*
 A fork or vfork creates a new process.  follow-fork-mode can be:.*
 .*parent  - the original process is debugged after a fork.*
 .*child   - the new process is debugged after a fork.*
 The unfollowed process will continue to run..*
 By default, the debugger will follow the parent process..*"

     # Verify that we can set follow-fork-mode, using an abbreviation
     # for both the flag and its value.
     #
     gdb_test_no_output "set follow-fork ch"

     gdb_test "show follow-fork" \
 	"Debugger response to a program call of fork or vfork is \"child\".*" \
 	"set follow-fork, using abbreviations"

     # Verify that we cannot set follow-fork-mode to nonsense.
     #
     gdb_test "set follow-fork chork" "Undefined item: \"chork\".*" \
 	"set follow-fork to nonsense is prohibited"

     gdb_test_no_output "set follow-fork parent" "reset parent"

     # Check that fork catchpoints are supported, as an indicator for whether
     # fork-following is supported.
     if [runto_main] then { check_fork_catchpoints }

     # Test the basic follow-fork functionality using all combinations of
     # values for follow-fork-mode and detach-on-fork, using either a
     # breakpoint or single-step to execute past the fork.
     #
     # The first loop should be sufficient to test the defaults.  There
     # is no need to test using the defaults in other permutations (e.g.
     # "default" "on", "parent" "default", etc.).
     foreach cmd {"next 2" "continue"} {
         test_follow_fork "default" "default" $cmd
     }

     # Now test all explicit permutations.
     foreach who {"parent" "child"} {
 	foreach detach {"on" "off"} {
 	    foreach cmd {"next 2" "continue"} {
 		test_follow_fork $who $detach $cmd
 	    }
 	}
     }

     # Catchpoint tests.

     # Restart to eliminate any effects of the follow-fork tests.
     clean_restart $testfile
     gdb_test_no_output "set verbose"

     # Test the ability to catch a fork, specify that the child be
     # followed, and continue.  Make the catchpoint permanent.
     #
     if [runto_main] then { catch_fork_child_follow }

     # Test that parent breakpoints are successfully detached from the
     # child at fork time, even if the user removes them from the
     # breakpoints list after stopping at a fork catchpoint.
     if [runto_main] then { catch_fork_unpatch_child }

     # Test the ability to catch a fork, specify via a -do clause that
     # the parent be followed, and continue.  Make the catchpoint temporary.
     #
     if [runto_main] then { tcatch_fork_parent_follow }
 }

 # This is a test of gdb's ability to follow the parent, child or both
 # parent and child of a Unix fork() system call.
 #
 do_fork_tests

 return 0
	# Copyright 1997-2020 Free Software Foundation, Inc.

	# This program is free software; you can redistribute it and/or modify
	# it under the terms of the GNU General Public License as published by
	# the Free Software Foundation; either version 3 of the License, or
	# (at your option) any later version.
	#
	# This program is distributed in the hope that it will be useful,
	# but WITHOUT ANY WARRANTY; without even the implied warranty of
	# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	# GNU General Public License for more details.
	#
	# You should have received a copy of the GNU General Public License
	# along with this program. If not, see <http://www.gnu.org/licenses/>.

	# Until "set follow-fork-mode" and "catch fork" are implemented on
	# other targets...
	#
	if { ![istarget "--linux"] && ![istarget "--openbsd"] } then {
	continue
	}

	# Test relies on checking follow-fork output. Do not run if gdb debug is
	# enabled as it will be redirected to the log.
	if [gdb_debug_enabled] {
	untested "debug is enabled"
	return 0
	}

	standard_testfile

	if {[prepare_for_testing "failed to prepare" $testfile $srcfile debug]} {
	return -1
	}

	proc check_fork_catchpoints {} {
	global gdb_prompt

	# Verify that the system supports "catch fork".
	gdb_test "catch fork" "Catchpoint \[0-9\]* \\(fork\\)" "insert first fork catchpoint"
	set has_fork_catchpoints 0
	gdb_test_multiple "continue" "continue to first fork catchpoint" {
	-re ".Your system does not support this type\r\nof catchpoint.$gdb_prompt $" {
	unsupported "continue to first fork catchpoint"
	}
	-re ".Catchpoint.$gdb_prompt $" {
	set has_fork_catchpoints 1
	pass "continue to first fork catchpoint"
	}
	}

	if {$has_fork_catchpoints == 0} {
	unsupported "fork catchpoints"
	return -code return
	}
	}

	# Test follow-fork to ensure that the correct process is followed, that
	# the followed process stops where it is expected to stop, that processes
	# are detached (or not) as expected, and that the inferior list has the
	# expected contents after following the fork. WHO is the argument to
	# the 'set follow-fork-mode' command, DETACH is the argument to the
	# 'set detach-on-fork' command, and CMD is the GDB command used to
	# execute the program past the fork. If the value of WHO or DETACH is
	# 'default', the corresponding GDB command is skipped for that test.
	# The value of CMD must be either 'next 2' or 'continue'.
	proc test_follow_fork { who detach cmd } {
	global gdb_prompt
	global srcfile
	global testfile

	with_test_prefix "follow $who, detach $detach, command \"$cmd\"" {

	# Start a new debugger session each time so defaults are legitimate.
	clean_restart $testfile

	if ![runto_main] {
	untested "could not run to main"
	return -1
	}

	# The "Detaching..." and "Attaching..." messages may be hidden by
	# default.
	gdb_test_no_output "set verbose"

	# Set follow-fork-mode if we aren't using the default.
	if {$who == "default"} {
	set who "parent"
	} else {
	gdb_test_no_output "set follow-fork $who"
	}

	gdb_test "show follow-fork" \
	"Debugger response to a program call of fork or vfork is \"$who\"."

	# Set detach-on-fork mode if we aren't using the default.
	if {$detach == "default"} {
	set detach "on"
	} else {
	gdb_test_no_output "set detach-on-fork $detach"
	}

	gdb_test "show detach-on-fork" \
	"Whether gdb will detach.* fork is $detach."

	# Set a breakpoint after the fork if we aren't single-stepping
	# past the fork.
	if {$cmd == "continue"} {
	set bp_after_fork [gdb_get_line_number "set breakpoint here"]
	gdb_test "break ${srcfile}:$bp_after_fork" \
	"Breakpoint., line $bp_after_fork." \
	"set breakpoint after fork"
	}

	# Set up the output we expect to see after we run.
	set expected_re ""
	if {$who == "child"} {
	set expected_re "\\\[Attaching after.* fork to.*"
	if {$detach == "on"} {
	append expected_re "\\\[Detaching after fork from .*"
	}
	append expected_re "set breakpoint here.*"
	} elseif {$who == "parent" && $detach == "on"} {
	set expected_re "\\\[Detaching after fork from .set breakpoint here."
	} else {
	set expected_re ".set breakpoint here."
	}

	# Test running past and following the fork, using the parameters
	# set above.
	gdb_test $cmd $expected_re "$cmd past fork"

	# Check that we have the inferiors arranged correctly after
	# following the fork.
	set resume_unfollowed 0
	if {$who == "parent" && $detach == "on"} {

	# Follow parent / detach child: the only inferior is the parent.
	gdb_test "info inferiors" "\\* 1 .* process.*"

	} elseif {$who == "parent" && $detach == "off"} {

	# Follow parent / keep child: two inferiors under debug, the
	# parent is the current inferior.
	gdb_test "info inferiors" "\\* 1 .process. 2 .process."

	gdb_test "inferior 2" "Switching to inferior 2 .*"
	set resume_unfollowed 1

	} elseif {$who == "child" && $detach == "on"} {

	# Follow child / detach parent: the child is under debug and is
	# the current inferior. The parent is listed but is not under
	# debug.
	gdb_test "info inferiors" " 1 .<null>.\\* 2 .process."

	} elseif {$who == "child" && $detach == "off"} {

	# Follow child / keep parent: two inferiors under debug, the
	# child is the current inferior.
	gdb_test "info inferiors" " 1 .process.\\* 2 .process."

	gdb_test "inferior 1" "Switching to inferior 1 .*"
	set resume_unfollowed 1
	}

	if {$resume_unfollowed == 1} {
	if {$cmd == "next 2"} {

	gdb_continue_to_end "continue unfollowed inferior to end"

	} elseif {$cmd == "continue"} {

	gdb_continue_to_breakpoint \
	"continue unfollowed inferior to bp" \
	".* set breakpoint here.*"
	}
	}
	}
	}

	proc catch_fork_child_follow {} {
	global gdb_prompt
	global srcfile

	set bp_after_fork [gdb_get_line_number "set breakpoint here"]

	gdb_test "catch fork" "Catchpoint \[0-9\]* \\(fork\\)" \
	"explicit child follow, set catch fork"

	# Verify that the catchpoint is mentioned in an "info breakpoints",
	# and further that the catchpoint mentions no process id.
	#
	set test_name "info shows catchpoint without pid"
	gdb_test_multiple "info breakpoints" "$test_name" {
	-re ".catchpoint.keep y.*fork\[\r\n\]+$gdb_prompt $" {
	pass "$test_name"
	}
	}

	gdb_test "continue" \
	"Catchpoint \[0-9\]* \\(forked process \[0-9\]\\),." \
	"explicit child follow, catch fork"

	# Verify that the catchpoint is mentioned in an "info breakpoints",
	# and further that the catchpoint managed to capture a process id.
	#
	set test_name "info shows catchpoint without pid"
	gdb_test_multiple "info breakpoints" "$test_name" {
	-re ".catchpoint.keep y.fork, process.$gdb_prompt $" {
	pass "$test_name"
	}
	}

	gdb_test_no_output "set follow-fork child"

	gdb_test "tbreak ${srcfile}:$bp_after_fork" \
	"Temporary breakpoint., line $bp_after_fork." \
	"set follow-fork child, tbreak"

	set expected_re "\\\[Attaching after.* fork to.*\\\[Detaching after fork from"
	append expected_re ".* at .$bp_after_fork."
	gdb_test "continue" $expected_re "set follow-fork child, hit tbreak"

	# The parent has been detached; allow time for any output it might
	# generate to arrive, so that output doesn't get confused with
	# any expected debugger output from a subsequent testpoint.
	#
	exec sleep 1

	gdb_test "delete breakpoints" \
	"" \
	"set follow-fork child, cleanup" \
	"Delete all breakpoints. \\(y or n\\) $" \
	"y"
	}

	proc catch_fork_unpatch_child {} {
	global gdb_prompt
	global srcfile

	set bp_exit [gdb_get_line_number "at exit"]

	gdb_test "break callee" "file .$srcfile, line ." \
	"unpatch child, break at callee"
	gdb_test "catch fork" "Catchpoint \[0-9\]* \\(fork\\)" \
	"unpatch child, set catch fork"

	gdb_test "continue" \
	"Catchpoint \[0-9\]* \\(forked process \[0-9\]\\),." \
	"unpatch child, catch fork"

	# Delete all breakpoints and catchpoints.
	delete_breakpoints

	# Force $srcfile as the current GDB source can be in glibc sourcetree.
	gdb_test "break $srcfile:$bp_exit" \
	"Breakpoint .file .$srcfile, line .*" \
	"unpatch child, breakpoint at exit call"

	gdb_test_no_output "set follow-fork child" \
	"unpatch child, set follow-fork child"

	set test "unpatch child, unpatched parent breakpoints from child"
	gdb_test_multiple "continue" $test {
	-re "at exit.*$gdb_prompt $" {
	pass "$test"
	}
	-re "SIGTRAP.*$gdb_prompt $" {
	fail "$test"

	# Explicitly kill this child, so we can continue gracefully
	# with further testing...
	send_gdb "kill\n"
	gdb_expect {
	-re ".Kill the program being debugged.y or n. $" {
	send_gdb "y\n"
	gdb_expect -re "$gdb_prompt $" {}
	}
	}
	}
	}
	}

	proc tcatch_fork_parent_follow {} {
	global gdb_prompt
	global srcfile

	set bp_after_fork [gdb_get_line_number "set breakpoint here"]

	gdb_test "catch fork" "Catchpoint \[0-9\]* \\(fork\\)" \
	"explicit parent follow, set tcatch fork"

	# ??rehrauer: I don't yet know how to get the id of the tcatch
	# via this script, so that I can add a -do list to it. For now,
	# do the follow stuff after the catch happens.

	gdb_test "continue" \
	"Catchpoint \[0-9\]* \\(forked process \[0-9\]\\),." \
	"explicit parent follow, tcatch fork"

	gdb_test_no_output "set follow-fork parent"

	gdb_test "tbreak ${srcfile}:$bp_after_fork" \
	"Temporary breakpoint., line $bp_after_fork." \
	"set follow-fork parent, tbreak"

	gdb_test "continue" \
	"\\\[Detaching after fork from.* at .$bp_after_fork." \
	"set follow-fork parent, hit tbreak"

	# The child has been detached; allow time for any output it might
	# generate to arrive, so that output doesn't get confused with
	# any expected debugger output from a subsequent testpoint.
	#
	exec sleep 1

	gdb_test "delete breakpoints" \
	"" \
	"set follow-fork parent, cleanup" \
	"Delete all breakpoints. \\(y or n\\) $" \
	"y"
	}

	proc do_fork_tests {} {
	global gdb_prompt
	global testfile

	# Verify that help is available for "set follow-fork-mode".
	#
	gdb_test "help set follow-fork-mode" \
	"Set debugger response to a program call of fork or vfork..*
	A fork or vfork creates a new process. follow-fork-mode can be:.*
	.parent - the original process is debugged after a fork.
	.child - the new process is debugged after a fork.
	The unfollowed process will continue to run..*
	By default, the debugger will follow the parent process..*"

	# Verify that we can set follow-fork-mode, using an abbreviation
	# for both the flag and its value.
	#
	gdb_test_no_output "set follow-fork ch"

	gdb_test "show follow-fork" \
	"Debugger response to a program call of fork or vfork is \"child\".*" \
	"set follow-fork, using abbreviations"

	# Verify that we cannot set follow-fork-mode to nonsense.
	#
	gdb_test "set follow-fork chork" "Undefined item: \"chork\".*" \
	"set follow-fork to nonsense is prohibited"

	gdb_test_no_output "set follow-fork parent" "reset parent"

	# Check that fork catchpoints are supported, as an indicator for whether
	# fork-following is supported.
	if [runto_main] then { check_fork_catchpoints }

	# Test the basic follow-fork functionality using all combinations of
	# values for follow-fork-mode and detach-on-fork, using either a
	# breakpoint or single-step to execute past the fork.
	#
	# The first loop should be sufficient to test the defaults. There
	# is no need to test using the defaults in other permutations (e.g.
	# "default" "on", "parent" "default", etc.).
	foreach cmd {"next 2" "continue"} {
	test_follow_fork "default" "default" $cmd
	}

	# Now test all explicit permutations.
	foreach who {"parent" "child"} {
	foreach detach {"on" "off"} {
	foreach cmd {"next 2" "continue"} {
	test_follow_fork $who $detach $cmd
	}
	}
	}

	# Catchpoint tests.

	# Restart to eliminate any effects of the follow-fork tests.
	clean_restart $testfile
	gdb_test_no_output "set verbose"

	# Test the ability to catch a fork, specify that the child be
	# followed, and continue. Make the catchpoint permanent.
	#
	if [runto_main] then { catch_fork_child_follow }

	# Test that parent breakpoints are successfully detached from the
	# child at fork time, even if the user removes them from the
	# breakpoints list after stopping at a fork catchpoint.
	if [runto_main] then { catch_fork_unpatch_child }

	# Test the ability to catch a fork, specify via a -do clause that
	# the parent be followed, and continue. Make the catchpoint temporary.
	#
	if [runto_main] then { tcatch_fork_parent_follow }
	}

	# This is a test of gdb's ability to follow the parent, child or both
	# parent and child of a Unix fork() system call.
	#
	do_fork_tests

	return 0