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Full Discussion: Newline in ANSI-C standard functions
Top Forums Programming Newline in ANSI-C standard functions Post 303020299 by yifangt on Monday 16th of July 2018 11:49:35 AM
Old 07-16-2018
Thanks Jim and Corona:
I was not sure the NULL terminator was handled correctly.
If str1 precedes str2 in memory and each one is word-aligned, then the last character you write to str1[128] effectively cause the end of of str1 to be the actual end of str2. This is quite twisting to me!! Now my understanding come to this:

1) Doing strncpy() first caused no NUL terminator, and gave me buffer overflow and strcpy() could not run at all.
2) Instead, doing strcpy() first the correct NUL terminator is ensured, then the following strncpy() seems working which still does not provide NUL terminator. But, because the program exits, just the problem did not show up.

Is this correct?
Blindly using strncpy because people call strcpy "bad" is worse than just using strcpy in the first place.

I do not know the risk of strcpy() or the correct use of strncpy(). They just happened to come to my exercise. I thought figure out the details may help understanding what's going on in the memory, which is why I tried memset(). Thanks again.
Last edited by yifangt; 07-16-2018 at 01:06 PM..
 

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LEARN ABOUT DEBIAN

set_color

set_color(1)							       fish							      set_color(1)

NAME

       set_color - set_color - set the terminal color

set_color - set the terminal color
   Synopsis
       set_color [-v --version] [-h --help] [-b --background COLOR] [COLOR]

   Description
       Change the foreground and/or background color of the terminal. COLOR is one of black, red, green, brown, yellow, blue, magenta, purple,
       cyan, white and normal.

       o -b, --background Set the background color

       o -c, --print-colors Prints a list of all valid color names

       o -h, --help Display help message and exit

       o -o, --bold Set bold or extra bright mode

       o -u, --underline Set underlined mode

       o -v, --version Display version and exit

       Calling set_color normal will set the terminal color to whatever is the default color of the terminal.

       Some terminals use the --bold escape sequence to switch to a brighter color set. On such terminals, set_color white will result in a grey
       font color, while set_color --bold white will result in a white font color.

       Not all terminal emulators support all these features. This is not a bug in set_color but a missing feature in the terminal emulator.

       set_color uses the terminfo database to look up how to change terminal colors on whatever terminal is in use. Some systems have old and
       incomplete terminfo databases, and may lack color information for terminals that support it. Download and install the latest version of
       ncurses and recompile fish against it in order to fix this issue.

Version 1.23.1							  Sun Jan 8 2012						      set_color(1)
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