c - system function flaws -

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we using c in linux. there possibility system() function can behave in unexpected manner, when handle signals?

we found sometimes, system() function blocks execution or throws sigsegv.

e.g: 

system ( "/bin/mv b" );

are there known flaws in using system() explain this?

the system() function supposed well. behaviour pretty reliable long invoked correctly. has 2 modes of operation:

  1. check whether there command interpreter available - when argument null pointer.
  2. run command given, waiting command complete before returning.

so, system() statement blocks until shell runs command completes. on unix-like systems, command invoked effectively:

"sh", "-c", "...argument system...", null

this means string passed interpreted shell. how long takes depends on command executed. can consider using shell notations run command in background if need to:

system("( /bin/mv b & )");

there few circumstances system() generate sigsegv. have pass invalid pointer, pointer somewhere invalid in program.


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