Historically, many unices are set to either 128 or 256. These days I believe Linux is most often at either 256 or 1024 depending on the distribution and sysadmin tinkering. AFAIK the *BSD family tend to 256. I am unaware of PC or Mac defaults and whether they can be changed. IRIX was 256, Sun was 256, HP was 256; last I checked. If you keep it reasonable, say less than 100 you seem to be ok just about everywhere but the pathological cases.

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