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POShell Script - Segmentation Fault
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copied!<p>I've run into a bit of a stumper while trying to get a shell script working. I am trying to make a script that reads a line from a database and format into a text file to be used with another piece of software. The script needs to loop around 50 million times (large database), and it does so just fine until 5,500 to 5,800 iterations, then it develops a segmentation fault.<br> I've tried to trace the error with strace (The last few lines are below), but I'm not really sure what I'm looking at.<br></p> <pre><code>clone(child_stack=0,flags=CLONE_CHILD_CLEARTID|CLONE_CHILD_SETTID|SIGCHLD, child_tidptr=0xb76f8728) = 17547 close(4) = 0 close(5) = 0 pipe([4, 5]) = 0 clone(child_stack=0, flags=CLONE_CHILD_CLEARTID|CLONE_CHILD_SETTID|SIGCHLD, child_tidptr=0xb76f8728) = 17548 close(3) = 0 close(5) = 0 pipe([3, 5]) = 0 clone(child_stack=0, flags=CLONE_CHILD_CLEARTID|CLONE_CHILD_SETTID|SIGCHLD, child_tidptr=0xb76f8728) = 17549 close(4) = 0 close(5) = 0 pipe([4, 5]) = 0 clone(child_stack=0, flags=CLONE_CHILD_CLEARTID|CLONE_CHILD_SETTID|SIGCHLD, child_tidptr=0xb76f8728) = 17550 close(3) = 0 close(5) = 0 clone(child_stack=0, flags=CLONE_CHILD_CLEARTID|CLONE_CHILD_SETTID|SIGCHLD, child_tidptr=0xb76f8728) = 17551 close(4) = 0 close(-1) = -1 EBADF (Bad file descriptor) wait4(-1, [{WIFEXITED(s) && WEXITSTATUS(s) == 0}], 0, NULL) = 17546 --- SIGCHLD (Child exited) @ 0 (0) --- wait4(-1, [{WIFEXITED(s) && WEXITSTATUS(s) == 0}], 0, NULL) = 17547 wait4(-1, [{WIFEXITED(s) && WEXITSTATUS(s) == 0}], 0, NULL) = 17548 wait4(-1, [{WIFEXITED(s) && WEXITSTATUS(s) == 0}], 0, NULL) = 17549 wait4(-1, [{WIFEXITED(s) && WEXITSTATUS(s) == 0}], 0, NULL) = 17551 --- SIGCHLD (Child exited) @ 0 (0) --- wait4(-1, [{WIFEXITED(s) && WEXITSTATUS(s) == 0}], 0, NULL) = 17550 --- SIGCHLD (Child exited) @ 0 (0) --- wait4(-1, [{WIFEXITED(s) && WEXITSTATUS(s) == 0}], 0, NULL) = 17545 --- SIGCHLD (Child exited) @ 0 (0) --- write(1, "OK!\n", 4OK! ) = 4 pipe([3, 4]) = 0 clone(child_stack=0, flags=CLONE_CHILD_CLEARTID|CLONE_CHILD_SETTID|SIGCHLD, child_tidptr=0xb76f8728) = 17552 close(4) = 0 read(3, "10632\n", 128) = 6 read(3, "", 128) = 0 close(3) = 0 wait4(-1, [{WIFEXITED(s) && WEXITSTATUS(s) == 0}], 0, NULL) = 17552 --- SIGCHLD (Child exited) @ 0 (0) --- clone(child_stack=0, flags=CLONE_CHILD_CLEARTID|CLONE_CHILD_SETTID|SIGCHLD, child_tidptr=0xb76f8728) = 17553 wait4(-1, [{WIFEXITED(s) && WEXITSTATUS(s) == 0}], 0, NULL) = 17553 --- SIGCHLD (Child exited) @ 0 (0) --- write(1, "Preparing file 10632 of ", 24Preparing file 10632 of ) = 24 write(1, "51041073(7) ....", 1651041073(7) ....) = 16 pipe([3, 4]) = 0 clone(child_stack=0, flags=CLONE_CHILD_CLEARTID|CLONE_CHILD_SETTID|SIGCHLD, child_tidptr=0xb76f8728) = 17554 close(4) = 0 read(3, "8\n", 128) = 2 read(3, "", 128) = 0 close(3) = 0 wait4(-1, [{WIFEXITED(s) && WEXITSTATUS(s) == 0}], 0, NULL) = 17554 --- SIGCHLD (Child exited) @ 0 (0) --- pipe([3, 4]) = 0 clone(child_stack=0, flags=CLONE_CHILD_CLEARTID|CLONE_CHILD_SETTID|SIGCHLD, child_tidptr=0xb76f8728) = 17555 close(4) = 0 read(3, "", 128) = 0 close(3) = 0 wait4(-1, [{WIFSIGNALED(s) && WTERMSIG(s) == SIGSEGV}], 0, NULL) = 17555 --- SIGCHLD (Child exited) @ 0 (0) --- --- SIGSEGV (Segmentation fault) @ 0 (0) --- +++ killed by SIGSEGV +++ Segmentation fault </code></pre> <p>The script is below:</p> <pre><code>#!/bin/sh #----VARS---- prefix="10.0.3.2/read/" oprdir="/home/andrew/doc/read/" throttle=0 #---------------- x=5000 advcount=0 count=`curl "$prefix""count.php" 2> /dev/null` #----Funcs---- getline() { #Run curl to get the line of text #TODO -n echo -n "Preparing file" $x "of " if [ $advcount -ge 25 ] then count=`curl "$prefix""count.php" 2> /dev/null` advcount=0 fi echo -n $count"("$advcount")" "...." advcount=`expr $advcount + 1` line=`curl "$prefix""testfile-prep.php?x=$x" 2> /dev/null` if [ "$line" = "ERR ERROR: X OUTSIDE RECORDS." ] then echo "ERROR: X OUTSIDE DB... WAITING TO RETRY." sleep 60 getline fi prepline } prepline() { echo $line | sed 's/^[0-9]*\./\n./g' | sed 's/\([a-zA-Z]*\)\./\1\n./g' | sed 's/\,/\n\,/g' | sed 's/(\(.*\)/(\n\1/g' | sed 's/\(.*\))/\1\n)/g' | sed 's/ /\n/g'> out-0-$x.dat echo "OK!" #cat out-$x.dat advance } advance() { x=`expr $x + 1` sleep $throttle getline } cd "$oprdir" getline </code></pre> <p>Sorry for the novelette of information, any help is appreciated.</p>

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