Exercise 4.1 Examining Signal Priorities and Execution
How do I test the signals program?
I am not getting the results I expect:
My assumptions: ---------------------------------------------
I compile signals.c (no errors) & run signals exe
./signals
signals program runs & SHOULD (I think) sit waiting for incoming signals
I send to the signals process from another Terminal session using kill -n(thesignal) nnnn(the process)
and the program spits out a display when it gets the signal
---------------------------------------------------------------------------------
However I run ./signals & it displays & terminates:
phil@weeminty ~/Dropbox/LFS201/LABS $ gcc signals.c
phil@weeminty ~/Dropbox/LFS201/LABS $ ./signals
Installing signal handler and Raising signal for signal number:
1 2 3 4 5 6 7 8 -- 10 11 12 13 14 15 16
17 18 -- 20 21 22 23 24 25 26 27 28 29 30 31 -- -- 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48
49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64
Signal Number(Times Processed)
--------------------------------------------
1: 1 2: 1 3: 1 4: 1 5: 1 6: 1 7: 1 8: 1
9: 0 10: 1 11: 1 12: 1 13: 1 14: 1 15: 1 16: 1
17: 1 18: 0 19: 0 20: 1 21: 1 22: 1 23: 1 24: 1
25: 1 26: 1 27: 1 28: 1 29: 1 30: 1 31: 1 32: 0
33: 0 34: 3 35: 3 36: 3 37: 3 38: 3 39: 3 40: 3
41: 3 42: 3 43: 3 44: 3 45: 3 46: 3 47: 3 48: 3
49: 3 50: 3 51: 3 52: 3 53: 3 54: 3 55: 3 56: 3
57: 3 58: 3 59: 3 60: 3 61: 3 62: 3 63: 3 64: 3
History: Signal Number(Count Processed)
--------------------------------------------
4(1) 5(1) 7(1) 8(1) 11(1) 31(1) 1(1) 2(1)
3(1) 6(1) 10(1) 12(1) 13(1) 14(1) 15(1) 16(1)
17(1) 20(1) 21(1) 22(1) 23(1) 24(1) 25(1) 26(1)
27(1) 28(1) 29(1) 30(1) 34(1) 34(2) 34(3) 35(1)
35(2) 35(3) 36(1) 36(2) 36(3) 37(1) 37(2) 37(3)
38(1) 38(2) 38(3) 39(1) 39(2) 39(3) 40(1) 40(2)
40(3) 41(1) 41(2) 41(3) 42(1) 42(2) 42(3) 43(1)
43(2) 43(3) 44(1) 44(2) 44(3) 45(1) 45(2) 45(3)
46(1) 46(2) 46(3) 47(1) 47(2) 47(3) 48(1) 48(2)
48(3) 49(1) 49(2) 49(3) 50(1) 50(2) 50(3) 51(1)
51(2) 51(3) 52(1) 52(2) 52(3) 53(1) 53(2) 53(3)
54(1) 54(2) 54(3) 55(1) 55(2) 55(3) 56(1) 56(2)
56(3) 57(1) 57(2) 57(3) 58(1) 58(2) 58(3) 59(1)
59(2) 59(3) 60(1) 60(2) 60(3) 61(1) 61(2) 61(3)
62(1) 62(2) 62(3) 63(1) 63(2) 63(3) 64(1) 64(2)
64(3)
phil@weeminty ~/Dropbox/LFS201/LABS $ ps -elf |grep signals
0 S phil 9893 9846 0 80 0 - 3556 pipe_w 10:10 pts/1 00:00:00 grep --color=auto signals
phil@weeminty ~/Dropbox/LFS201/LABS $
I have downloaded the latest version from
https://training.linuxfoundation.org/cm/LFS201/
User LFTraining & pwPenguin2014
with the same result (above).
Tried it as a background process: ./signals &
Tried it using sudo": sudo ./signals
tried gcc signals.c -o mysignals
thus:
phil@weeminty ~/Dropbox/LFS201/LABS $ gcc signals.c -o mysignals
phil@weeminty ~/Dropbox/LFS201/LABS $ l
a.out* mysignals* signals* signals.c was_signals.c
phil@weeminty ~/Dropbox/LFS201/LABS $ ./mysignals
Installing signal handler and Raising signal for signal number:
1 2 3 4 5 6 7 8 -- 10 11 12 13 14 15 16
17 18 -- 20 21 22 23 24 25 26 27 28 29 30 31 -- -- 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48
49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64
Signal Number(Times Processed)
--------------------------------------------
1: 1 2: 1 3: 1 4: 1 5: 1 6: 1 7: 1 8: 1
9: 0 10: 1 11: 1 12: 1 13: 1 14: 1 15: 1 16: 1
17: 1 18: 0 19: 0 20: 1 21: 1 22: 1 23: 1 24: 1
25: 1 26: 1 27: 1 28: 1 29: 1 30: 1 31: 1 32: 0
33: 0 34: 3 35: 3 36: 3 37: 3 38: 3 39: 3 40: 3
41: 3 42: 3 43: 3 44: 3 45: 3 46: 3 47: 3 48: 3
49: 3 50: 3 51: 3 52: 3 53: 3 54: 3 55: 3 56: 3
57: 3 58: 3 59: 3 60: 3 61: 3 62: 3 63: 3 64: 3
History: Signal Number(Count Processed)
--------------------------------------------
4(1) 5(1) 7(1) 8(1) 11(1) 31(1) 1(1) 2(1)
3(1) 6(1) 10(1) 12(1) 13(1) 14(1) 15(1) 16(1)
17(1) 20(1) 21(1) 22(1) 23(1) 24(1) 25(1) 26(1)
27(1) 28(1) 29(1) 30(1) 34(1) 34(2) 34(3) 35(1)
35(2) 35(3) 36(1) 36(2) 36(3) 37(1) 37(2) 37(3)
38(1) 38(2) 38(3) 39(1) 39(2) 39(3) 40(1) 40(2)
40(3) 41(1) 41(2) 41(3) 42(1) 42(2) 42(3) 43(1)
43(2) 43(3) 44(1) 44(2) 44(3) 45(1) 45(2) 45(3)
46(1) 46(2) 46(3) 47(1) 47(2) 47(3) 48(1) 48(2)
48(3) 49(1) 49(2) 49(3) 50(1) 50(2) 50(3) 51(1)
51(2) 51(3) 52(1) 52(2) 52(3) 53(1) 53(2) 53(3)
54(1) 54(2) 54(3) 55(1) 55(2) 55(3) 56(1) 56(2)
56(3) 57(1) 57(2) 57(3) 58(1) 58(2) 58(3) 59(1)
59(2) 59(3) 60(1) 60(2) 60(3) 61(1) 61(2) 61(3)
62(1) 62(2) 62(3) 63(1) 63(2) 63(3) 64(1) 64(2)
64(3)
phil@weeminty ~/Dropbox/LFS201/LABS $ ps -elf |grep mysignals
0 S phil 10941 9846 0 80 0 - 3556 pipe_w 10:37 pts/1 00:00:00 grep --color=auto mysignals
phil@weeminty ~/Dropbox/LFS201/LABS $
--------------------------------------------------------------------------------------------------
Comments
-
HI:
The excercise is doing exactly what it says it is doing. It is not designed to sit and wait for any user input such as sending a signal to it. It sends a boatload of signals while they are blocked and then unblocks and records what happens. Please read the description after the code source, which says:
Prints out statistics including: – The total number of times each signal was received. – The order in which the signals were received, noting each time the total number of times that signal had been received up to that point.
0
Categories
- All Categories
- 207 LFX Mentorship
- 207 LFX Mentorship: Linux Kernel
- 735 Linux Foundation IT Professional Programs
- 339 Cloud Engineer IT Professional Program
- 167 Advanced Cloud Engineer IT Professional Program
- 66 DevOps Engineer IT Professional Program
- 132 Cloud Native Developer IT Professional Program
- 122 Express Training Courses
- 122 Express Courses - Discussion Forum
- 5.9K Training Courses
- 40 LFC110 Class Forum - Discontinued
- 66 LFC131 Class Forum
- 39 LFD102 Class Forum
- 221 LFD103 Class Forum
- 17 LFD110 Class Forum
- 33 LFD121 Class Forum
- 17 LFD133 Class Forum
- 6 LFD134 Class Forum
- 17 LFD137 Class Forum
- 70 LFD201 Class Forum
- 3 LFD210 Class Forum
- 2 LFD210-CN Class Forum
- 2 LFD213 Class Forum - Discontinued
- 128 LFD232 Class Forum - Discontinued
- 1 LFD233 Class Forum
- 3 LFD237 Class Forum
- 23 LFD254 Class Forum
- 689 LFD259 Class Forum
- 109 LFD272 Class Forum
- 3 LFD272-JP クラス フォーラム
- 10 LFD273 Class Forum
- 109 LFS101 Class Forum
- LFS111 Class Forum
- 2 LFS112 Class Forum
- 1 LFS116 Class Forum
- 3 LFS118 Class Forum
- 3 LFS142 Class Forum
- 3 LFS144 Class Forum
- 3 LFS145 Class Forum
- 1 LFS146 Class Forum
- 2 LFS147 Class Forum
- 8 LFS151 Class Forum
- 1 LFS157 Class Forum
- 13 LFS158 Class Forum
- 5 LFS162 Class Forum
- 1 LFS166 Class Forum
- 3 LFS167 Class Forum
- 1 LFS170 Class Forum
- 1 LFS171 Class Forum
- 2 LFS178 Class Forum
- 2 LFS180 Class Forum
- 1 LFS182 Class Forum
- 4 LFS183 Class Forum
- 30 LFS200 Class Forum
- 737 LFS201 Class Forum - Discontinued
- 2 LFS201-JP クラス フォーラム
- 17 LFS203 Class Forum
- 116 LFS207 Class Forum
- 1 LFS207-DE-Klassenforum
- LFS207-JP クラス フォーラム
- 301 LFS211 Class Forum
- 55 LFS216 Class Forum
- 49 LFS241 Class Forum
- 43 LFS242 Class Forum
- 37 LFS243 Class Forum
- 13 LFS244 Class Forum
- 1 LFS245 Class Forum
- 45 LFS250 Class Forum
- 1 LFS250-JP クラス フォーラム
- LFS251 Class Forum
- 145 LFS253 Class Forum
- LFS254 Class Forum
- LFS255 Class Forum
- 6 LFS256 Class Forum
- LFS257 Class Forum
- 1.2K LFS258 Class Forum
- 9 LFS258-JP クラス フォーラム
- 116 LFS260 Class Forum
- 154 LFS261 Class Forum
- 41 LFS262 Class Forum
- 82 LFS263 Class Forum - Discontinued
- 15 LFS264 Class Forum - Discontinued
- 11 LFS266 Class Forum - Discontinued
- 23 LFS267 Class Forum
- 18 LFS268 Class Forum
- 29 LFS269 Class Forum
- 200 LFS272 Class Forum
- 1 LFS272-JP クラス フォーラム
- LFS274 Class Forum
- 3 LFS281 Class Forum
- 7 LFW111 Class Forum
- 257 LFW211 Class Forum
- 178 LFW212 Class Forum
- 12 SKF100 Class Forum
- SKF200 Class Forum
- 791 Hardware
- 199 Drivers
- 68 I/O Devices
- 37 Monitors
- 98 Multimedia
- 174 Networking
- 91 Printers & Scanners
- 85 Storage
- 754 Linux Distributions
- 82 Debian
- 67 Fedora
- 16 Linux Mint
- 13 Mageia
- 23 openSUSE
- 147 Red Hat Enterprise
- 31 Slackware
- 13 SUSE Enterprise
- 351 Ubuntu
- 465 Linux System Administration
- 39 Cloud Computing
- 71 Command Line/Scripting
- Github systems admin projects
- 91 Linux Security
- 78 Network Management
- 101 System Management
- 47 Web Management
- 56 Mobile Computing
- 17 Android
- 28 Development
- 1.2K New to Linux
- 1K Getting Started with Linux
- 366 Off Topic
- 114 Introductions
- 171 Small Talk
- 20 Study Material
- 534 Programming and Development
- 293 Kernel Development
- 223 Software Development
- 1.1K Software
- 212 Applications
- 182 Command Line
- 3 Compiling/Installing
- 405 Games
- 311 Installation
- 79 All In Program
- 79 All In Forum
Upcoming Training
-
August 20, 2018
Kubernetes Administration (LFS458)
-
August 20, 2018
Linux System Administration (LFS301)
-
August 27, 2018
Open Source Virtualization (LFS462)
-
August 27, 2018
Linux Kernel Debugging and Security (LFD440)