Unix Tricks

Useful unix character sequences

In "unix," to monitor system calls, use strace or truss.
In "C++", to string out in full justified hex with type safety:

my_type val = foo;

cout << hex << setiosflags(ios::right) << setw(2*sizeof(my_type)) << val << endl;
On Mac, to blank screen (for instance to reset 30" display):
Ctrl-Shift-Eject
In Unix, to see tree-based listing of files:
tree
In old Centos, when running metacity, to show minimized windows:
Alt-Esc
On Mac, to move window to another Space, either hit F8 to view all spaces, and drag,
Click on window, holding button, and then
Ctrl-<#>
On Mac OS X Lion, to move buggy window that is stuck off-screen because of secondary display disconnect
On menu bar, hold down "Option" Key and do window->Arrange in Front
In "linux," to scan for hosts in local domain:
nmap -sP 192.168.1.1-255
In "linux," to download an http file without a browser, use wget.
In "emacs", to do regular expression replacement, i.e.,
of x? --> y?

M-x query-replace-regexp RET
x$[0-9]$ RET
y\1 RET
In "emacs" to manipulate rectangular regions, mark first corner, move to second,

Ctrl-x r k (kill)
Ctrl-x r y (yank)
to view ps with the full process inheritance tree, try

ps -faux
to print strings inside a binary try:

strings < binary >
to print symbols inside a binary try:

nm < binary >
to look inside an rpm:

rpm -q -l -p < .rpm file >
to goto page inside Acrobat Reader 7.0:

shift-ctrl-N
In "sh," to call another program, blah, with the same arguments that were passed to the shell script:

#!/bin/sh
blah $*

#!/bin/sh
blah "$@"

which also passes arguments with embedded character sequences.

In unix, compare two directories:

find . -type f -not -exec cmp {} /path/to/dir2/{} ";" -print
In unix, remove from repository:

find . -iname "*.foo.pdf" -exec rm {} \; -exec cvs remove {} \;
In "gcc," to show all of the macros that are defined for a given platform:

gcc -dM -E test.c

gas foo.s -ahlm

In "emacs," to enable conservative indentation, add this to your .emacs files

add-hook 'c++-mode-hook
          (function (lambda ()
                       (c-set-style "k&r")
                       (setq c-basic-offset 2)
                    )))
for more information, look at
"/usr/uns/share/emacs/19.34/lisp/cc-mode.el"
In emacs, to show last typed commands: C-h l
In "gcc," stringification:

#define WARN_IF(EXP) \
do { if (EXP) \
fprintf (stderr, "Warning: " #EXP "\n"); }
while (0)
In "emacs," to create a macro : Ctrl-X "(" keys Ctrl-X ")" Ctrl-X "(" keys Ctrl-X ")"

see emacs faq, #116

In "make," to run a command without having it barf on error :

rule:
-mkdir blah
In "gmake," fancy automatic variables.

%.s: %.S
$(RGCC) -E $< -o $@

%.lnk: %.o
$(GEO) link 0 16 0 $^ libarch.a -o $@

In "gmake," a strlen function.
strlen = $(strip $(shell /bin/echo -n $(1) | /usr/bin/wc -c))
MAX_FIGURE = 10
FIGURE_DIGITS := $(call strlen,$(MAX_FIGURE))
To use CVS over ssh:
setenv CVS_RSH ssh
alias cvs cvs -d :ext:user_name@host:cvsroot_path
To see what happened in the CVS repository between two and four hours ago:

cvs diff -D "2 hour ago" -D "4 hour ago"

LD_LIBRARY_PATH can be overridden by /etc/ld.so.conf, followed by

ldconfig to update the .so cache

When your terminal gets messed up because you tried to print out binary stuff, type "reset"

ps, so that more does not get screwed up:
ps -www -aux | more
To capture screen in X.
xwd > blah
xpr blah > blah.ps
use xv to convert to ppm or whatever
To sync up the times when make sucks.
rdate < time server >
To highlight a zephyr message, hold down shift.

To view x resources:
editres
To check for non-updated files with cvs:
bash -c "cvs status 2> /dev/null | grep Status | grep Need"