Simple Terminal from SuckLess
You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.

201 lines
8.4 KiB

7 years ago
  1. ## Why does st not handle utmp entries?
  2. Use the excellent tool of [utmp](https://git.suckless.org/utmp/) for this task.
  3. ## Some _random program_ complains that st is unknown/not recognised/unsupported/whatever!
  4. It means that st doesn’t have any terminfo entry on your system. Chances are
  5. you did not `make install`. If you just want to test it without installing it,
  6. you can manually run `tic -sx st.info`.
  7. ## Nothing works, and nothing is said about an unknown terminal!
  8. * Some programs just assume they’re running in xterm i.e. they don’t rely on
  9. terminfo. What you see is the current state of the “xterm compliance”.
  10. * Some programs don’t complain about the lacking st description and default to
  11. another terminal. In that case see the question about terminfo.
  12. ## How do I scroll back up?
  13. * Using a terminal multiplexer.
  14. * `st -e tmux` using C-b [
  15. * `st -e screen` using C-a ESC
  16. * Using the excellent tool of [scroll](https://git.suckless.org/scroll/).
  17. * Using the scrollback [patch](https://st.suckless.org/patches/scrollback/).
  18. ## I would like to have utmp and/or scroll functionality by default
  19. You can add the absolute patch of both programs in your config.h
  20. file. You only have to modify the value of utmp and scroll variables.
  21. ## Why doesn't the Del key work in some programs?
  22. Taken from the terminfo manpage:
  23. If the terminal has a keypad that transmits codes when the keys
  24. are pressed, this information can be given. Note that it is not
  25. possible to handle terminals where the keypad only works in
  26. local (this applies, for example, to the unshifted HP 2621 keys).
  27. If the keypad can be set to transmit or not transmit, give these
  28. codes as smkx and rmkx. Otherwise the keypad is assumed to
  29. always transmit.
  30. In the st case smkx=E[?1hE= and rmkx=E[?1lE>, so it is mandatory that
  31. applications which want to test against keypad keys send these
  32. sequences.
  33. But buggy applications (like bash and irssi, for example) don't do this. A fast
  34. solution for them is to use the following command:
  35. $ printf '\033[?1h\033=' >/dev/tty
  36. or
  37. $ tput smkx
  38. In the case of bash, readline is used. Readline has a different note in its
  39. manpage about this issue:
  40. enable-keypad (Off)
  41. When set to On, readline will try to enable the
  42. application keypad when it is called. Some systems
  43. need this to enable arrow keys.
  44. Adding this option to your .inputrc will fix the keypad problem for all
  45. applications using readline.
  46. If you are using zsh, then read the zsh FAQ
  47. <http://zsh.sourceforge.net/FAQ/zshfaq03.html#l25>:
  48. It should be noted that the O / [ confusion can occur with other keys
  49. such as Home and End. Some systems let you query the key sequences
  50. sent by these keys from the system's terminal database, terminfo.
  51. Unfortunately, the key sequences given there typically apply to the
  52. mode that is not the one zsh uses by default (it's the "application"
  53. mode rather than the "raw" mode). Explaining the use of terminfo is
  54. outside of the scope of this FAQ, but if you wish to use the key
  55. sequences given there you can tell the line editor to turn on
  56. "application" mode when it starts and turn it off when it stops:
  57. function zle-line-init () { echoti smkx }
  58. function zle-line-finish () { echoti rmkx }
  59. zle -N zle-line-init
  60. zle -N zle-line-finish
  61. Putting these lines into your .zshrc will fix the problems.
  62. ## How can I use meta in 8bit mode?
  63. St supports meta in 8bit mode, but the default terminfo entry doesn't
  64. use this capability. If you want it, you have to use the 'st-meta' value
  65. in TERM.
  66. ## I cannot compile st in OpenBSD
  67. OpenBSD lacks librt, despite it being mandatory in POSIX
  68. <http://pubs.opengroup.org/onlinepubs/9699919799/utilities/c99.html#tag_20_11_13>.
  69. If you want to compile st for OpenBSD you have to remove -lrt from config.mk, and
  70. st will compile without any loss of functionality, because all the functions are
  71. included in libc on this platform.
  72. ## The Backspace Case
  73. St is emulating the Linux way of handling backspace being delete and delete being
  74. backspace.
  75. This is an issue that was discussed in suckless mailing list
  76. <https://lists.suckless.org/dev/1404/20697.html>. Here is why some old grumpy
  77. terminal users wants its backspace to be how he feels it:
  78. Well, I am going to comment why I want to change the behaviour
  79. of this key. When ASCII was defined in 1968, communication
  80. with computers was done using punched cards, or hardcopy
  81. terminals (basically a typewriter machine connected with the
  82. computer using a serial port). ASCII defines DELETE as 7F,
  83. because, in punched-card terms, it means all the holes of the
  84. card punched; it is thus a kind of 'physical delete'. In the
  85. same way, the BACKSPACE key was a non-destructive backspace,
  86. as on a typewriter. So, if you wanted to delete a character,
  87. you had to BACKSPACE and then DELETE. Another use of BACKSPACE
  88. was to type accented characters, for example 'a BACKSPACE `'.
  89. The VT100 had no BACKSPACE key; it was generated using the
  90. CONTROL key as another control character (CONTROL key sets to
  91. 0 b7 b6 b5, so it converts H (code 0x48) into BACKSPACE (code
  92. 0x08)), but it had a DELETE key in a similar position where
  93. the BACKSPACE key is located today on common PC keyboards.
  94. All the terminal emulators emulated the difference between
  95. these keys correctly: the backspace key generated a BACKSPACE
  96. (^H) and delete key generated a DELETE (^?).
  97. But a problem arose when Linus Torvalds wrote Linux. Unlike
  98. earlier terminals, the Linux virtual terminal (the terminal
  99. emulator integrated in the kernel) returned a DELETE when
  100. backspace was pressed, due to the VT100 having a DELETE key in
  101. the same position. This created a lot of problems (see [1]
  102. and [2]). Since Linux has become the king, a lot of terminal
  103. emulators today generate a DELETE when the backspace key is
  104. pressed in order to avoid problems with Linux. The result is
  105. that the only way of generating a BACKSPACE on these systems
  106. is by using CONTROL + H. (I also think that emacs had an
  107. important point here because the CONTROL + H prefix is used
  108. in emacs in some commands (help commands).)
  109. From point of view of the kernel, you can change the key
  110. for deleting a previous character with stty erase. When you
  111. connect a real terminal into a machine you describe the type
  112. of terminal, so getty configures the correct value of stty
  113. erase for this terminal. In the case of terminal emulators,
  114. however, you don't have any getty that can set the correct
  115. value of stty erase, so you always get the default value.
  116. For this reason, it is necessary to add 'stty erase ^H' to your
  117. profile if you have changed the value of the backspace key.
  118. Of course, another solution is for st itself to modify the
  119. value of stty erase. I usually have the inverse problem:
  120. when I connect to non-Unix machines, I have to press CONTROL +
  121. h to get a BACKSPACE. The inverse problem occurs when a user
  122. connects to my Unix machines from a different system with a
  123. correct backspace key.
  124. [1] http://www.ibb.net/~anne/keyboard.html
  125. [2] http://www.tldp.org/HOWTO/Keyboard-and-Console-HOWTO-5.html
  126. ## But I really want the old grumpy behaviour of my terminal
  127. Apply [1].
  128. [1] https://st.suckless.org/patches/delkey
  129. ## Why do images not work in st (in programs such as w3m)?
  130. This is a terrible hack that overdraws an image on top of the terminal emulator
  131. window. It also relies on a very specific way the terminal draws it's contents.
  132. A more proper (but limited way) would be using sixels. Which st doesn't
  133. support.
  134. ## BadLength X error in Xft when trying to render emoji
  135. Xft makes st crash when rendering color emojis with the following error:
  136. "X Error of failed request: BadLength (poly request too large or internal Xlib length error)"
  137. Major opcode of failed request: 139 (RENDER)
  138. Minor opcode of failed request: 20 (RenderAddGlyphs)
  139. Serial number of failed request: 1595
  140. Current serial number in output stream: 1818"
  141. This is a known bug in Xft (not st) which happens on some platforms and
  142. combination of particular fonts and fontconfig settings.
  143. See also:
  144. https://gitlab.freedesktop.org/xorg/lib/libxft/issues/6
  145. https://bugs.freedesktop.org/show_bug.cgi?id=107534
  146. https://bugzilla.redhat.com/show_bug.cgi?id=1498269
  147. The solution is to remove color emoji fonts or disable this in the fontconfig
  148. XML configuration. As an ugly workaround (which may work only on newer
  149. fontconfig versions (FC_COLOR)), the following code can be used to mask color
  150. fonts:
  151. FcPatternAddBool(fcpattern, FC_COLOR, FcFalse);
  152. Please don't bother reporting this bug to st, but notify the upstream Xft
  153. developers about fixing this bug.