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Alin Năstac wrote: |
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> I remember that one time I had to split a command like dohtml |
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> "${S}"/something/*.{png,html} because the line was too long. At that |
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> time, bash had a limit of 32K. Now is what ... 1M? |
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|
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from execve(2): |
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|
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Limits on size of arguments and environment |
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|
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Most Unix implementations impose some limit on the total size of the |
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command-line argument (argv) and environment (envp) strings that may be |
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passed to a new program. POSIX.1 allows an implementation to advertise |
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this limit using the ARG_MAX constant (either defined in <limits.h> or |
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available at run time using the call sysconf(_SC_ARG_MAX)). |
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|
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On Linux prior to kernel 2.6.23, the memory used to store the |
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environment and argument strings was limited to 32 pages (defined by the |
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kernel constant MAX_ARG_PAGES). On architectures with a 4-kB page size, |
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this yields a maximum size of 128 kB. |
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|
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On kernel 2.6.23 and later, most architectures support a size limit |
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derived from the soft RLIMIT_STACK resource limit (see getrlimit(2)). |
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For these architectures, the total size is limited to 1/4 of the allowed |
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stack size, the limit per string is 32 pages (the kernel constant |
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MAX_ARG_STRLEN), and the maximum number of strings is 0x7FFFFFFF. (This |
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change allows programs to have a much larger argument and/or environment |
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list. Imposing the 1/4-limit ensures that the new program always has |
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some stack space.) Architectures with no memory management unit are |
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excepted: they maintain the limit that was in effect before kernel 2.6.23. |
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|
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Cheers, |
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-jkt |
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|
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-- |
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cd /local/pub && more beer > /dev/mouth |
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