Re: The * character (was: Latex )
On Thu, 08 Aug 1996 10:34:27 +1000 Mark Phillips ([EMAIL PROTECTED]
edu.au) wrote:
It would be helpful if you could tell us what version of the packages
you have installed. For example, if you would run this commands:
dpkg -l *tex*
I noticed that this doesn't work under tcsh, but does work under
bash. Is there a difference between how the * character is treated
under the two shells?
By default, bash expands shell metacharacters (*?[]) only if they're a match
({} rules are the exception, they're always expanded). Otherwise, bash passes
the metacharacters to the invoked program.
Tcsh will complain and abort if it cannot expand some metacharacters. You need
to quote them.
Solution: always quote shell metacharacters when you want to pass them to a
program.
Phil.
Re: The * character (was: Latex )
It would be helpful if you could tell us what version of the packages you have installed. For example, if you would run this commands: dpkg -l *tex* I noticed that this doesn't work under tcsh, but does work under bash. Is there a difference between how the * character is treated under the two shells? '*tex*' works with both shells. bash will not replace a clobber pattern with the empty string if no match is found, tcsh does (AFAIK). bash(1) # Pathname Expansion # After word splitting, unless the -f option has been set, # bash scans each word for the characters *, ?, and [. If # one of these characters appears, then the word is regarded # as a pattern, and replaced with an alphabetically sorted # list of pathnames matching the pattern. If no matching # pathnamesarefound,and the shell variable # allow_null_glob_expansion is unset, the word is left # unchanged. If the variable is set, and no matches are # found, the word is removed. When a pattern is used for # pathname generation, the character `.'' at the start of # a name or immediately following a slash must be matched # explicitly, unless the shell variable glob_dot_filenames # is set. The slash character must always be matched # explicitly. In other cases, the `.'' character is not # treated specially. and bash(1) set # -u Treat unset variables as an error when per- # forming parameter expansion. If expansion # is attempted on an unset variable, the # shell prints an error message, and, if not # interactive, exits with a non-zero status. # Greetings Bernd -- (OO) -- [EMAIL PROTECTED] -- ( .. ) [EMAIL PROTECTED],ka.sub.org} http://home.pages.de/~eckes/ o--o *plush* 2048/A2C51749 [EMAIL PROTECTED] +4972573817 *plush* (OO) If privacy is outlawed only Outlaws have privacy
The * character (was: Latex )
Mark Phillips writes: It would be helpful if you could tell us what version of the packages you have installed. For example, if you would run this commands: dpkg -l *tex* I noticed that this doesn't work under tcsh, but does work under bash. Is there a difference between how the * character is treated under the two shells? It differs from shell to shell and even within a given shell: marin215# tcsh # echo *tex* echo: No match. # set nonomatch # echo *tex* *tex* # In csh, having nonomatch set asks the shell not to say it can't do a wildcard expansion but rather to pass the argument (as if it was quoted, then) to the command. The surest way to get consistent results is to quote ;-) Yves.
Re: The * character (was: Latex )
if you prefer the bash behavior of ignoring the pattern failure, just set nonomatch in tcsh or csh.
Re: The * character (was: Latex )
Hi Mark -- You said: in response to: Hi Mark -- You asked: because I'd said: It would be helpful if you could tell us what version of the packages you have installed. For example, if you would run this commands: dpkg -l *tex* I noticed that this doesn't work under tcsh, but does work under bash. Is there a difference between how the * character is treated under the two shells? What I'd written was actually not right for either shell. I should have written: dpkg -l *tex* The problem is that without the quotes, the shell expands the argument first, before handing it to dpkg. If there's a file in your current directory with a name that matches *tex*, then that file, and only that file, is fed to dpkg. This is not what's intended of course. So I tried the correct usage (with the quotes) under tcsh and it worked fine. But the interesting thing is that dpkg -l *tex* actually _works_ when run under bash, leading me to think that the bash shell doesn't expand the argument first. Are you sure you tried dpkg -l *tex* in a directory where you know there's a file whose name matches the pattern *tex*, and whose name is not that of a debian package? On my system both bash and tcsh behaved the same way. Susan
Re: The * character (was: Latex )
Hi Mark -- You said: Very strange. Here is what I did on my system under bash: (mark, destiny)$ ls Maelstromgnuchesscmaelstromxonix Maelstrom_sound gnuchessnmirrormagic xp-replay acm gnuchessrnethack xpat2 acms gnuchessxpostprintxpilot cmailgnugopxboard xpilots fortune gnushogi xasteroids xshogi game gnushogirxbattle xsok gnuangnushogixxboard xtet42 gnuchess kill-acmsxinvadersxtron (mark, destiny)$ dpkg -l *tex* Desired=Unknown/Install/Remove/Purge | Status=Not/Installed/Config-files/Unpacked/Failed-config/Half-installed |/ Err?=(none)/Hold/Reinst-required/X=both-problems (Status,Err: uppercase=ba d) ||/ NameVersionDescription +++-===-==-== == un X11-text-viewer none (no description available) pn amslatexnone (no description available) pn amstex none (no description available) pn auctex none (no description available) pn bibtex none (no description available) pn gettext none (no description available) pn hyperlatex none (no description available) pn latex none (no description available) pn latex2e-doc none (no description available) pn latex2rtf none (no description available) ii nb-tex 2.1-1 NTeX package ii nb-texi 2.1-1 NTeX package ii ntex2.1-1 NTeX package ii nx-etex 2.1-1 NTeX package ii nx-mtex 2.1-1 NTeX package un tex none (no description available) pn texbin none (no description available) pn texidoc none (no description available) ii texinfo 3.7-1 The GNU Project's documentation formatting s pn texlib none (no description available) pn texpsfntnone (no description available) pn textfm none (no description available) ii textutils 1.19-1 The GNU text file processsing utilities. ii untex 9210-4 Remove LaTeX commands from input. (Which incidently is the same as what I get when I use the quotes) What you got was correct. Your directory listing shows no files which match *tex*. Therefore, the shell couldn't expand *tex* to anything in your directory, and therefore passed the string *tex* to dpkg, which expanded it on its own. If: -- you have a file whose name matches *tex* in the current working directory, AND if the name of that file _is not_ the name of a Debian package, then dpkg wouldn't be able to infer its status. You'd get a message No packages found matching whatever file you had that matched *tex*. -- you have a file whose name matches *tex* in the current working directory, AND if the name of the file _is_ the name of a Debian package, then dpkg -l would be able to look up its status and report it. -- you do not have a file whose name matches *tex* in the current working directory, then the shell passes *tex* to dpkg, which expands the regexp in its administrative directories. HTH, Susan
Re: The * character (was: Latex )
But the interesting thing is that dpkg -l *tex* actually _works_ when run under bash, leading me to think that the bash shell doesn't expand the argument first. Are you sure you tried dpkg -l *tex* in a directory where you know there's a file whose name matches the pattern *tex*, and whose name is not that of a debian package? On my system both bash and tcsh behaved the same way. Very strange. Here is what I did on my system under bash: (mark, destiny)$ ls Maelstromgnuchesscmaelstromxonix Maelstrom_sound gnuchessnmirrormagic xp-replay acm gnuchessrnethack xpat2 acms gnuchessxpostprintxpilot cmailgnugopxboard xpilots fortune gnushogi xasteroids xshogi game gnushogirxbattle xsok gnuangnushogixxboard xtet42 gnuchess kill-acmsxinvadersxtron (mark, destiny)$ dpkg -l *tex* Desired=Unknown/Install/Remove/Purge | Status=Not/Installed/Config-files/Unpacked/Failed-config/Half-installed |/ Err?=(none)/Hold/Reinst-required/X=both-problems (Status,Err: uppercase=bad) ||/ NameVersionDescription +++-===-==- un X11-text-viewer none (no description available) pn amslatexnone (no description available) pn amstex none (no description available) pn auctex none (no description available) pn bibtex none (no description available) pn gettext none (no description available) pn hyperlatex none (no description available) pn latex none (no description available) pn latex2e-doc none (no description available) pn latex2rtf none (no description available) ii nb-tex 2.1-1 NTeX package ii nb-texi 2.1-1 NTeX package ii ntex2.1-1 NTeX package ii nx-etex 2.1-1 NTeX package ii nx-mtex 2.1-1 NTeX package un tex none (no description available) pn texbin none (no description available) pn texidoc none (no description available) ii texinfo 3.7-1 The GNU Project's documentation formatting s pn texlib none (no description available) pn texpsfntnone (no description available) pn textfm none (no description available) ii textutils 1.19-1 The GNU text file processsing utilities. ii untex 9210-4 Remove LaTeX commands from input. (Which incidently is the same as what I get when I use the quotes) Mark.
The * character (was: Latex )
It would be helpful if you could tell us what version of the packages you have installed. For example, if you would run this commands: dpkg -l *tex* I noticed that this doesn't work under tcsh, but does work under bash. Is there a difference between how the * character is treated under the two shells? Thanks, Mark.
Re: The * character (was: Latex )
Hi Mark -- You asked: because I'd said: It would be helpful if you could tell us what version of the packages you have installed. For example, if you would run this commands: dpkg -l *tex* I noticed that this doesn't work under tcsh, but does work under bash. Is there a difference between how the * character is treated under the two shells? What I'd written was actually not right for either shell. I should have written: dpkg -l *tex* The problem is that without the quotes, the shell expands the argument first, before handing it to dpkg. If there's a file in your current directory with a name that matches *tex*, then that file, and only that file, is fed to dpkg. This is not what's intended of course. So I tried the correct usage (with the quotes) under tcsh and it worked fine. Cheers, Susan
Re: The * character (was: Latex )
Hi Mark -- You asked: because I'd said: It would be helpful if you could tell us what version of the packages you have installed. For example, if you would run this commands: dpkg -l *tex* I noticed that this doesn't work under tcsh, but does work under bash. Is there a difference between how the * character is treated under the two shells? What I'd written was actually not right for either shell. I should have written: dpkg -l *tex* The problem is that without the quotes, the shell expands the argument first, before handing it to dpkg. If there's a file in your current directory with a name that matches *tex*, then that file, and only that file, is fed to dpkg. This is not what's intended of course. So I tried the correct usage (with the quotes) under tcsh and it worked fine. But the interesting thing is that dpkg -l *tex* actually _works_ when run under bash, leading me to think that the bash shell doesn't expand the argument first. Mark.
Re: The * character (was: Latex )
Mark, When using wildcards in bash, the shell attempts to expand them, but if it finds nothing that matches the specified pattern, it passes the wildcard string to the command. Quoting the wildcard pattern causes the shell to pass it as a single argument to the command. In your case, since there was no file in the directory you were executing from that matched the pattern *tex*, bash behaved as if you had quoted the pattern. Since I don't use tcsh, I couldn't say for certain, but my understanding is that it treats wildcards in a slightly different manner - always attempting the expansion and returning an error message if the no matches are found. To pass an argument containing wildcards, the pattern must be quoted. This would explain why: bash$ dpkg -l *tex* worked, and: tcsh% dpkg -l *tex* did not. In any case, as a matter of good style, you should always quote wildcards when you don't want them expanded - even if you know you can get away without it. Hope this clarifies things... Gerry
Re: The * character (was: Latex )
Mark Phillips wrote: : : you have installed. For example, if you would run this commands: : dpkg -l *tex* : I noticed that this doesn't work under tcsh, but does work under : bash. Is there a difference between how the * character is treated : under the two shells? Under sh-lish shells `*' expands to all files, if any, or to '*' itsself, if no files/dirs match. Under csh-lish shells `*' expands to all files, if any, or to _nothing_ (and a note `no match') if nothing matches. AFAIK ... Heiko -- email : [EMAIL PROTECTED] [EMAIL PROTECTED] [EMAIL PROTECTED] pgp : A1 7D F6 7B 69 73 48 35 E1 DE 21 A7 A8 9A 77 92 finger: [EMAIL PROTECTED] [EMAIL PROTECTED]
Re: The * character (was: Latex )
On Thu, 8 Aug 1996, Mark Phillips wrote: dpkg -l *tex* I noticed that this doesn't work under tcsh, but does work under bash. Is there a difference between how the * character is treated under the two shells? Yes, there is a difference when the globbing doesn't expand to anything. In this case bash passes the word with the wildcards while tcsh just errors. For example: $ ls $ echo *tex* *tex* $ ./nosuchfile *tex* bash: ./nosuchfile: No such file or directory. $ tcsh echo *tex* echo: No match. ./nosuchfile *tex* ./nosuchfile: No match. tcsh is pretty broken to issue make it seem as if commands that don't exist are issuing errors. Guy
