Linux development tools-gdb (I) and linux development tools-gdb

Linux development tools-gdb (I) and linux development tools-gdb
Iii. gdb debugging (I) 01.gdb: gdb is short for GNU debugger and is a programming debugging task. Function: start the program and run the program as needed according to user-defined requirements; the program to be debugged can be stopped at the breakpoint specified by the user (the breakpoint can be a conditional expression); when the program stops, it can detect what happens in the program at this time; dynamically change the execution environment of the program. # Vi smiple. c # include <stdio. h> # include <stdlib. h> long func (int n); int main (int argc, char * argv []) {printf ("Entering main... \ n "); int I; long result = 0; for (I = 1; I <= 100; I ++) {result + = I ;} printf ("result [1-100] = % ld \ n", result); printf ("result [1-10]", func (10); return 0 ;} long func (int n) {long sum = 0; int I; for (I = 1; I <n; I ++) {sum + = 1 ;}return sum ;}: wq # gcc-Wall-g (to generate debugging and display the source file) simple. c-o simple #. /simple # gdb Simple (gdb) list (display all source code) (gdb) l (same as above) (gdb) break 10 (set breakpoints in line 10th) (gdb) info break (view breakpoint Information) -- ib (abbreviation) (gdb) B func (Set breakpoint at function entry) (gdb) run -- r (run to breakpoint) (gdb) step -- s (single-step tracking) (gdb) print I -- p I (print the current value of I) (gdb) p resultresult = 3 (gdb) p I (gdb) s (gdb) until (jump out of the for loop, the next statement of the loop) (gdb) c (continue to run to the next breakpoint) (gdb) Press enter directly, use the previous command (gdb) finish (end one-step debugging) # vi Makefile. PHONY: clean allCC = gccCFLAGS =-Wall-gBIN = simple mainall: $ (BIN) $ (CC) $ (CFLAGS)-c $ <-O $ @ main: main. o search. o $ (CC) $ (CFLAGS) & ^-o $ @ clean: rm-f *. o $ (BIN): wq # gdb simple (gdb) r a B c (add startup parameters to the program) (gdb) list fun (view the function source code of fun) (gdb) list file: fun (view the fun function source code in the file) 02. set breakpoint and Observation Point break row number break funbreak file: row number break file: funbreak if <condition>-when the condition is set, the program stops info break (I B) -Check that the checkpoint watch expr-variable expr value has changed, and the program stops deleting n-delete the checkpoint 03. one-step debugging of continue (c)-running to the next breakpoint step (s)-One-step tracing, entering the function, similar to step innext (n)-One-step tracking in VC, do not enter the function, Class Similar to step outfinish in VC-run the program until the current function is completed. The stack address, return value, and parameters returned by the function are printed. Until-when tired of one-step tracking in a loop body, this command can run the program until it exits print (p) to view the runtime variables and expressions