FISH@LIVERPOOL.AC.UK (10/19/90)
I have recently discovered a problem with ksh88. The print command has a flag -s that allows you to place things into the history file, i.e. print -s Hello there will place "Hello there" in the history file. The manual claims that echo uses the echo program which means that echo -s should print the string -s. For reasons explained below this is the preferred behaviour. However, it would appear that echo has been aliased to print, even though the manual would claim that this is not the case and echo is /bin/echo like in the Bourne shell and earlier versions of the K shell. Has anyone had this problem and how did you crack it? alias -x echo /bin/echo dosen't work and gives an error neither does defining a function although you can do this without an error message. Background: I have been trying to write a simple training manual for users that has a worked example that uses the flag -s. This is to show some of the dangers in using test with things like [ -s = -s ], which works in n some implementations and not others. Unfortunately the way round it I discuss using `if echo $arg | grep -s -e -s' no longer works if echo -s dosen't send -s to stdout. I don't want to use the [[ ]] construct because we don't have ksh88 across the whole site, even though I recomend its use if available. Thanks in advance. Any ideas? Francis Fish Programmer / Analyst Liverpool University Computer Laboratory fish@uk.ac.liverpool
gt0178a@prism.gatech.EDU (Jim Burns) (10/20/90)
in article <90292.140155FISH@LIVERPOOL.AC.UK>, FISH@LIVERPOOL.AC.UK says: > alias -x echo /bin/echo dosen't work and gives an error It will if you include the '=': alias -x echo=/bin/echo -- BURNS,JIM Georgia Institute of Technology, Box 30178, Atlanta Georgia, 30332 uucp: ...!{decvax,hplabs,ncar,purdue,rutgers}!gatech!prism!gt0178a Internet: gt0178a@prism.gatech.edu
lml@cbnews.att.com (L. Mark Larsen) (10/21/90)
In article <90292.140155FISH@LIVERPOOL.AC.UK>, FISH@LIVERPOOL.AC.UK writes: > I have recently discovered a problem with ksh88. The print command has a flag > -s that allows you to place things into the history file, i.e. > > print -s Hello there > > will place "Hello there" in the history file. The manual claims that echo > uses the echo program which means that echo -s should print the string -s. I tried this with ksh86, ksh88, ksh88e and "echo -s" prints "-s". Of course, it is possible that your version of ksh was compiled to exclude echo - it is an option afterall. If so, there might be an alias (poorly defined) for it in your environment. Try "alias echo" or "whence -v echo" to see. A proper alias for echo (if needed) is: alias echo='print -' The '-' ends the argument string for print so, with this alias, your attempt to do "echo -s" will work as expected. No need to call /bin/echo. > Thanks in advance. Any ideas? > > Francis Fish L. Mark Larsen lml@atlas.att.com