Cygwin Utilities
Cygwin comes with a number of command-line utilities that are
used to manage the UNIX emulation portion of the Cygwin environment.
While many of these reflect their UNIX counterparts, each was written
specifically for Cygwin.
cygcheck
Usage: cygcheck [-s] [-v] [-r] [-h] [program ...]
-c check current package setup
-h give help about the info
-s system information
-v verbose output (indented) (for -s or programs)
-r registry search (requires -s)
-V version info
You must at least give either -s or a program name
The cygcheck program is a diagnostic utility
that examines your system and reports the information that is
significant to the proper operation of Cygwin programs. It can give
information about a specific program (or program) you are trying to
run, general system information, or both. If you list one or more
programs on the command line, it will diagnose the runtime environment
of that program or programs. If you specify the -s
option, it will give general system information. If you specify
-s and list one or more programs on the command line,
it reports on both.
The -c option causes the "program" arguments
to be interpreted as package names. cygcheck will
report the current version of the package that you specify. With no
arguments, cygcheck will report on all packages.
The cygcheck program should be used to send
information about your system to Cygnus for troubleshooting (if your
support representative requests it). When asked to run this command,
include all the options plus any commands you are having trouble with,
and save the output so that you can mail it to Cygnus, like
this:
C:\Cygnus> cygcheck -s -v -r -h > tocygnus.txt
The -v option causes the output to be more
verbose. What this means is that additional information will be
reported which is usually not interesting, such as the internal
version numbers of DLLs, additional information about recursive DLL
usage, and if a file in one directory in the PATH also occurs in other
directories on the PATH.
The -r option causes
cygcheck to search your registry for information
that is relevent to Cygnus programs. These registry entries are the
ones that have "Cygnus" in the name. If you are paranoid about
privacy, you may remove information from this report, but please keep
in mind that doing so makes it harder for Cygnus to diagnose your
problems.
The -h option prints additional helpful
messages in the report, at the beginning of each section. It also
adds table column headings. While this is useful information, it also
adds some to the size of the report, so if you want a compact report
or if you know what everything is already, just leave this out.
cygpath
Usage: cygpath.exe [-p|--path] (-u|--unix)|(-w|--windows [-s|--short-name]) filename
-a|--absolute output absolute path
-c|--close handle close handle (for use in captured process)
-f|--file file read file for input path information
-i|--ignore ignore missing argument
-p|--path filename argument is a path
-s|--short-name print Windows short form of filename
-u|--unix print Unix form of filename
-v|--version output version information and exit
-w|--windows print Windows form of filename
-A|--allusers use `All Users' instead of current user for -D, -P
-D|--desktop output `Desktop' directory and exit
-P|--smprograms output Start Menu `Programs' directory and exit
-S|--sysdir output system directory and exit
-W|--windir output `Windows' directory and exit
The cygpath program is a utility that
converts Windows native filenames to Cygwin POSIX-style pathnames and
back. It can be used when a Cygwin program needs to pass a file name
to a native Windows program, or expects to get a file name from a
native Windows program. You may use the long or short option names
interchangeably, even though only the short ones are described
here.
The -u and -w options
indicate whether you want a conversion from Windows to UNIX (POSIX)
format (-u) or a conversion from UNIX (POSIX) to
Windows format (-w). You must give exactly
one of these. To give neither or both is an error. Use the
-s option in combination with the -w
option to convert to Windows short form.
The -p option means that you want to convert
a path-style string rather than a single filename. For example, the
PATH environment variable is semicolon-delimited in Windows, but
colon-delimited in UNIX. By giving -p you are
instructing cygpath to convert between these
formats.
The -i option supresses the print out of the
usage message if no filename argument was given. It can be used in
make file rules converting variables to a proper format that may be
omitted.
Example cygpath usage
#!/bin/sh
for i in `echo *.exe | sed 's/\.exe/.cc/'`
do
notepad "`cygpath -w $i`"
done
The capital options
-D, -P, -S, and
-W output directories used by Windows that are not the
same on all systems, for example -S might output
C:\WINNT\SYSTEM32 or C:\WINDOWS\SYSTEM. The -A option
forces use of the "All Users" directories instead of the current user
for the -D and -P options.
On Win9x systems with only a single user, -A has no
effect; -D and -AD would have the
same output.
kill
Usage: kill [-f] [-sigN] pid1 [pid2 ...]
The kill program allows you to send arbitrary
signals to other Cygwin programs. The usual purpose is to end a
running program from some other window when ^C won't work, but you can
also send program-specified signals such as SIGUSR1 to trigger actions
within the program, like enabling debugging or re-opening log files.
Each program defines the signals they understand.
Note that, unless you specific the -f option,
the "pid" values are the Cygwin pids, not the Windows pids. To get a
list of running programs and their Cygwin pids, use the Cygwin
ps program. ps -W will display
all windows pids.
To send a specific signal, use the -signN
option, either with a signal number or a signal name (minus the "SIG"
part), like these examples:
Using the kill command
$ kill 123
$ kill -1 123
$ kill -HUP 123
$ kill -f 123
Here is a list of available signals, their numbers, and some
commentary on them, from the file
<sys/signal.h>, which should be considered
the official source of this information.
SIGHUP 1 hangup
SIGINT 2 interrupt
SIGQUIT 3 quit
SIGILL 4 illegal instruction (not reset when caught)
SIGTRAP 5 trace trap (not reset when caught)
SIGABRT 6 used by abort
SIGEMT 7 EMT instruction
SIGFPE 8 floating point exception
SIGKILL 9 kill (cannot be caught or ignored)
SIGBUS 10 bus error
SIGSEGV 11 segmentation violation
SIGSYS 12 bad argument to system call
SIGPIPE 13 write on a pipe with no one to read it
SIGALRM 14 alarm clock
SIGTERM 15 software termination signal from kill
SIGURG 16 urgent condition on IO channel
SIGSTOP 17 sendable stop signal not from tty
SIGTSTP 18 stop signal from tty
SIGCONT 19 continue a stopped process
SIGCHLD 20 to parent on child stop or exit
SIGCLD 20 System V name for SIGCHLD
SIGTTIN 21 to readers pgrp upon background tty read
SIGTTOU 22 like TTIN for output if (tp->t_local<OSTOP)
SIGIO 23 input/output possible signal
SIGPOLL 23 System V name for SIGIO
SIGXCPU 24 exceeded CPU time limit
SIGXFSZ 25 exceeded file size limit
SIGVTALRM 26 virtual time alarm
SIGPROF 27 profiling time alarm
SIGWINCH 28 window changed
SIGLOST 29 resource lost (eg, record-lock lost)
SIGUSR1 30 user defined signal 1
SIGUSR2 31 user defined signal 2
mkgroup
usage: mkgroup [options] [domain]
This program prints a /etc/group file to stdout
Options:
-l,--local print local group information
-d,--domain print global group information from the domain
specified (or from the current domain if there is
no domain specified)
-o,--id-offset offset change the default offset (10000) added to uids
in domain accounts.
-s,--no-sids don't print SIDs in pwd field
(this affects ntsec)
-u,--users print user list in gr_mem field
-?,--help print this message
One of `-l' or `-d' must be given on NT/W2K.
The mkgroup program can be used to help
configure your Windows system to be more UNIX-like by creating an
initial /etc/group substitute (some commands need this
file) from your system information. It only works on NT.
To initially set up your machine,
you'd do something like this:
Setting up the groups file
$ mkdir /etc
$ mkgroup -l > /etc/group
Note that this information is static. If you change the group
information in your system, you'll need to regenerate the group file
for it to have the new information.
The -d and -l options
allow you to specify where the information comes from, either the
local machine or the default (or given) domain.
mkpasswd
Usage: mkpasswd [options] [domain]
Usage: mkpasswd [OPTION]... [domain]
This program prints a /etc/passwd file to stdout
Options:
-l,--local print local user accounts
-d,--domain print domain accounts (from current domain
if no domain specified)
-o,--id-offset offset change the default offset (10000) added to uids
in domain accounts.
-g,--local-groups print local group information too
if no domain specified
-m,--no-mount don't use mount points for home dir
-s,--no-sids don't print SIDs in GCOS field
(this affects ntsec)
-p,--path-to-home path if user account has no home dir, use
path instead of /home/
-u,--username username only return information for the specified user
-?,--help displays this message
One of `-l', `-d' or `-g' must be given on NT/W2K.
The mkpasswd program can be used to help
configure your Windows system to be more UNIX-like by creating an
initial /etc/passwd substitute (some commands
need this file) from your system information. It only works on NT.
To initially set up your machine, you'd do something like this:
Setting up the passwd file
$ mkdir /etc
$ mkpasswd -l > /etc/passwd
Note that this information is static. If you change the user
information in your system, you'll need to regenerate the passwd file
for it to have the new information.
The -d and -l options
allow you to specify where the information comes from, either the
local machine or the default (or given) domain.
passwd
Usage passwd [name]
passwd [-x max] [-n min] [-i inact] [-L len]
passwd {-l|-u|-S} name
-x max set max age of passwords
-n min set min age of passwords
-i inact disables account after inact days of expiry
-L len set min password length
-l lock an account
-u unlock an account
-S show account information
passwd changes passwords for user accounts.
A normal user may only change the password for their own account,
the administrators may change the password for any account.
passwd also changes account information, such as
password expiry dates and intervals.
Password changes: The user is first prompted for their old
password, if one is present. This password is then encrypted and
compared against the stored password. The user has only one chance to
enter the correct password. The administrators are permitted to
bypass this step so that forgotten passwords may be changed.
The user is then prompted for a replacement password.
passwd will prompt again and compare the second entry
against the first. Both entries are require to match in order for the
password to be changed.
After the password has been entered, password aging information
is checked to see if the user is permitted to change their password
at this time. If not, passwd refuses to change the
password and exits.
Password expiry and length: The password aging information may be
changed by the administrators with the -x,
-n and -i options. The
-x option is used to set the maximum number of days
a password remains valid. After max days, the
password is required to be changed. The -n option is
used to set the minimum number of days before a password may be changed.
The user will not be permitted to change the password until
min days have elapsed. The -i
option is used to disable an account after the password has been expired
for a number of days. After a user account has had an expired password
for inact days, the user may no longer sign on to
the account. Allowed values for the above options are 0 to 999. The
-L option sets the minimum length of allowed passwords
for users, which doesn't belong to the administrators group, to
len characters. Allowed values for the minimum
password length are 0 to 14. In any of the above cases, a value of 0
means `no restrictions'.
Account maintenance: User accounts may be locked and unlocked with the
-l and -u flags. The
-l option disables an account. The -u
option re-enables an account.
The account status may be given with the -S
option. The status information is self explanatory.
Limitations: Users may not be able to change their password on
some systems.
mount
Usage mount
mount [options] <win32path> <posixpath>
-b, --binary text files are equivalent to binary files
(newline = \n)
-c, --change-cygdrive-prefix change the cygdrive path prefix to <posixpath>
-f, --force force mount, don't warn about missing mount
point directories
-i, --import-old-mounts copy old registry mount table mounts into the current
mount areas
-p, --show-cygdrive-prefix show user and/or system cygdrive path prefix
-s, --system add mount point to system-wide registry location
-t, --text (default) text files get \r\n line endings
-u, --user (default) add mount point to user registry location
-x, --executable treat all files under mount point as executables
-X, --cygwin-executable treat all files under mount point as cygwin
executables
-m, --mount-commands write mount commands to replace user and
system mount points and cygdrive prefixes
When invoked without any arguments, mount displays the current mount table.
The mount program is used to map your drives
and shares onto Cygwin's simulated POSIX directory tree, much like as is
done by mount commands on typical UNIX systems. Please see
for more information on the concepts
behind the Cygwin POSIX file system and strategies for using
mounts.
Using mount
If you just type mount with no parameters, it
will display the current mount table for you.
Displaying the current set of mount points
c:\cygnus\> mount
Device Directory Type Flags
D: /d user textmode
C: / system textmode
In this example, the C
drive is the POSIX root and D drive is mapped to
/d. Note that in this case, the root mount is a
system-wide mount point that is visible to all users running Cygwin
programs, whereas the /d mount is only visible
to the current user.
The mount utility is also the mechanism for
adding new mounts to the mount table. The following example
demonstrates how to mount the directory
C:\cygnus\cygwin-b20\H-i586-cygwin32\bin
to /bin and the network directory
\\pollux\home\joe\data to /data.
/bin is assumed to already exist.
Adding mount points
c:\cygnus\> ls /bin /data
ls: /data: No such file or directory
c:\cygnus\> mount C:\cygnus\cygwin-b20\H-i586-cygwin32\bin /bin
c:\cygnus\> mount \\pollux\home\joe\data /data
Warning: /data does not exist!
c:\cygnus\> mount
Device Directory Type Flags
\\pollux\home\joe\data /data user textmode
C:\cygnus\cygwin-b20\H-i586-cygwin32\bin /bin user textmode
D: /d user textmode
\\.\tape1: /dev/st1 user textmode
\\.\tape0: /dev/st0 user textmode
\\.\b: /dev/fd1 user textmode
\\.\a: /dev/fd0 user textmode
C: / system textmode
c:\cygnus\> ls /bin/sh
/bin/sh
Note that mount was invoked from the Windows
command shell in the previous example. In many Unix shells, including
bash, it is legal and convenient to use the forward "/" in Win32
pathnames since the "\" is the shell's escape character.
The "-s" flag to mount is used to add a mount
in the system-wide mount table used by all Cygwin users on the system,
instead of the user-specific one. System-wide mounts are displayed
by mount as being of the "system" type, as is the
case for the / partition in the last example.
Under Windows NT, only those users with Administrator priviledges are
permitted to modify the system-wide mount table.
Note that a given POSIX path may only exist once in the user
table and once in the global, system-wide table. Attempts to replace
the mount will fail with a busy error. The "-f" (force) flag causes
the old mount to be silently replaced with the new one. It will also
silence warnings about the non-existence of directories at the Win32
path location.
The "-b" flag is used to instruct Cygwin to treat binary and
text files in the same manner by default. Binary mode mounts are
marked as "binmode" in the Flags column of mount
output. By default, mounts are in text mode ("textmode" in the Flags
column).
The "-x" flag is used to instruct Cygwin that the mounted file
is "executable". If the "-x" flag is used with a directory then
all files in the directory are executable. Files ending in certain
extensions (.exe, .com, .bat, .cmd) are assumed to be executable
by default. Files whose first two characters begin with '#!' are
also considered to be executable. This option allows other files
to be marked as executable and avoids the overhead of opening each
file to check for a '#!'.
Cygdrive mount points
Whenever Cygwin cannot use any of the existing mounts to convert
from a particular Win32 path to a POSIX one, Cygwin will, instead,
convert to a POSIX path using a default mount point:
/cygdrive. For example, if Cygwin accesses
Z:\foo and the Z drive is not currently in the
mount table, then Z:\ will be accessible as
/cygdrive/Z. The default prefix of
/cygdrive may be changed via the
command.
The mount utility can be used to change this
default automount prefix through the use of the
"--change-cygdrive-prefix" flag. In the following example, we will
set the automount prefix to /:
Changing the default prefix
c:\cygnus\> mount --change-cygdrive-prefix /
Note that you if you set a new prefix in this manner, you can
specify the "-s" flag to make this the system-wide default prefix. By
default, the cygdrive-prefix applies only to the current user. In the
same way, you can specify the "-b" flag such that all new automounted
filesystems default to binary mode file accesses.
Limitations
Limitations: there is a hard-coded limit of 30 mount
points. Also, although you can mount to pathnames that do not start
with "/", there is no way to make use of such mount points.
Normally the POSIX mount point in Cygwin is an existing empty
directory, as in standard UNIX. If this is the case, or if there is a
place-holder for the mount point (such as a file, a symbolic link
pointing anywhere, or a non-empty directory), you will get the expected
behavior. Files present in a mount point directory before the mount
become invisible to Cygwin programs.
It is sometimes desirable to mount to a non-existent directory,
for example to avoid cluttering the root directory with names
such as
a, b, c
pointing to disks.
Although mount will give you a warning, most
everything will work properly when you refer to the mount point
explicitly. Some strange effects can occur however.
For example if your current working directory is
/dir,
say, and /dir/mtpt is a mount point, then
mtpt will not show up in an ls
or
echo * command and find . will
not
find mtpt.
ps
Usage ps [-aefl] [-u uid]
-a, -e show processes of all users
-f show process uids, ppids
-l show process uids, ppids, pgids, winpids
-s short process listing
-u uid show processes owned by uid
-W show all windows processes, not just cygwin processes
The ps program gives the status of all the
Cygwin processes running on the system (ps = "process status"). Due
to the limitations of simulating a POSIX environment under Windows,
there is little information to give. The PID column is the process ID
you need to give to the kill command. The WINPID
column is the process ID that's displayed by NT's Task Manager
program.
umount
Usage umount [options] <posixpath>
-A, --remove-all-mounts remove all mounts
-c, --remove-cygdrive-prefix remove cygdrive prefix
-s, --system remove system mount
-S, --remove-system-mounts remove all system mounts
-u, --user remove user mount
-U, --remove-user-mounts remove all user mounts
The umount program removes mounts from the
mount table. If you specify a POSIX path that corresponds to a
current mount point, umount will remove it from the
user-specific registry area. The -s flag may be used to specify
removing the mount from the system-wide registry area instead
(Administrator priviledges are required).
The umount utility may also be used to remove
all mounts of a particular type. With the extended options it is
possible to remove all mounts, all automatically-mounted mounts, all
mounts in the current user's registry area, or all mounts in the
system-wide registry area (with Administrator privileges).
See ) for more information on the mount
table.
strace
Usage strace [options] program [args...]
-b, --buffer-size=SIZE set size of output file buffer
-d, --no-delta don't display the delta-t microsecond timestamp
-f, --trace-children also trace forked child processes
-h, --help display help info
-m, --mask=MASK set message filter mask
-n, --crack-error-numbers output descriptive text instead of error
numbers for Windows errors
-o, --output=FILENAME set output file to FILENAME
-p, --pid=pid attach to a running process
-S, --flush-period=PERIOD flush buffered strace output every PERIOD secs
-t, --timestamp use an absolute hh:mm:ss timestamp insted of the
default microsecond timestamp. Implies -d
-v, --version display version info
-w, --new-window spawn program under test in a new window
MASK can be any combination of the following mnemonics and/or hex values
(0x is optional). Combine masks with '+' or ',' like so:
--mask=wm+system,malloc+0x00800
Mnemonic Hex Corresponding Def Description
=========================================================================
all 0x00001 (_STRACE_ALL) All strace messages.
flush 0x00002 (_STRACE_FLUSH) Flush output buffer after each message.
inherit 0x00004 (_STRACE_INHERIT) Children inherit mask from parent.
uhoh 0x00008 (_STRACE_UHOH) Unusual or weird phenomenon.
syscall 0x00010 (_STRACE_SYSCALL) System calls.
startup 0x00020 (_STRACE_STARTUP) argc/envp printout at startup.
debug 0x00040 (_STRACE_DEBUG) Info to help debugging.
paranoid 0x00080 (_STRACE_PARANOID) Paranoid info.
termios 0x00100 (_STRACE_TERMIOS) Info for debugging termios stuff.
select 0x00200 (_STRACE_SELECT) Info on ugly select internals.
wm 0x00400 (_STRACE_WM) Trace Windows msgs (enable _strace_wm).
sigp 0x00800 (_STRACE_SIGP) Trace signal and process handling.
minimal 0x01000 (_STRACE_MINIMAL) Very minimal strace output.
exitdump 0x04000 (_STRACE_EXITDUMP) Dump strace cache on exit.
system 0x08000 (_STRACE_SYSTEM) Cache strace messages.
nomutex 0x10000 (_STRACE_NOMUTEX) Don't use mutex for synchronization.
malloc 0x20000 (_STRACE_MALLOC) Trace malloc calls.
thread 0x40000 (_STRACE_THREAD) Thread-locking calls.
The strace program executes a program, and
optionally the children of the program, reporting any Cygwin DLL output
from the program(s) to file. This program is mainly useful for debugging
the Cygwin DLL itself.
regtool
Regtool Copyright (c) 2000 Red Hat Inc
regtool -h - print this message
regtool [-v|-p|-k|-l] list [key] - list subkeys and values
-p=postfix, like ls -p, appends / postfix to key names
-k=keys, lists only keys
-l=values, lists only values
regtool [-v] add [key\subkey] - add new subkey
regtool [-v] remove [key] - remove key
regtool [-v|-q] check [key] - exit 0 if key exists, 1 if not
regtool [-i|-s|-e|-m] set [key\value] [data ...] - set value
-i=integer -s=string -e=expand-string -m=multi-string
regtool [-v] unset [key\value] - removes value from key
regtool [-q] get [key\value] - prints value to stdout
-q=quiet, no error msg, just return nonzero exit if key/value missing
keys are like \prefix\key\key\key\value, where prefix is any of:
root HKCR HKEY_CLASSES_ROOT
config HKCC HKEY_CURRENT_CONFIG
user HKCU HKEY_CURRENT_USER
machine HKLM HKEY_LOCAL_MACHINE
users HKU HKEY_USERS
example: \user\software\Microsoft\Clock\iFormat
The regtool program allows shell scripts
to access and modify the Windows registry. Note that modifying the
Windows registry is dangerous, and carelessness here can result
in an unusable system. Be careful.
The -v option means "verbose". For most
commands, this causes additional or lengthier messages to be printed.
Conversely, the -q option supresses error messages,
so you can use the exit status of the program to detect if a key
exists or not (for example).
The list command lists the subkeys and values
belonging to the given key. The add command adds a
new key. The remove command removes a key. Note
that you may need to remove everything in the key before you may
remove it, but don't rely on this stopping you from accidentally
removing too much. The check command checks to see
if a key exists (the exit code of the program is zero if it does,
nonzero if it does not).
The set command sets a value within a key.
-i means the value is an integer (DWORD).
-s means the value is a string.
-e means it's an expanding string (it contains
embedded environment variables). -m means it's a
multi-string (list). If you don't specify one of these, it tries to
guess the type based on the value you give. If it looks like a
number, it's a number. If it starts with a percent, it's an expanding
string. If you give multiple values, it's a multi-string. Else, it's
a regular string.
The unset command removes a value from a key.
The get command gets the value of a value of a key,
and prints it (and nothing else) to stdout. Note: if the value
doesn't exist, an error message is printed and the program returns a
non-zero exit code. If you give -q, it doesn't
print the message but does return the non-zero exit code.